Uhm, buddy, don't draw conclusions from thin air.
Thin air? Ok. Your whole post shows your depth of thought, reasoning and mild ignorance. I'll explain..
I've been around long enough to remember it all. Yes, standards are there for a reason, but many won't die a graceful death either.
Ok, Let's observe your reasoning.
Why does the latest generation of motherboards have DVI ports? There's really no need for it, yet there are so many brand new boards that have DVI ports.
That's easy to understand. DVI is still around as a standard because it's still relevant. The industrial/professional world upgrades it's motherboard more often than the displays they power. Additionally, as a general rule, two displays can be connected to a single DVI connector which is very useful. So where there is a demand, there will be a need for supply, more on that point in a moment.
There are even brand new boards with 9-pin serial ports on them ffs... It seems like some motherboard makers have run into a conundrum of not having enough things to stick on the rear I/O, so they just throw something else in, because...
Oh yes, there still are 9pin serial ports. There is a great deal of industrial systems and machines which were built with that data interface. Why? Because it's a standard and easy to use port. And unlike USB, a properly built 9pin serial cable can be screwed into it's port and will not easily come loose or fall out due to vibrations. It is a durable, well known and easily built standard port still in wide-spread use today. That limited, but significant, market sector will not be going away anytime soon either. It is FAR more cost effective to continue to support an older standard than to replace machines and hardware which continue to be useful and relevant 20, 30 and even 40 years after the computers they were originally designed to interface with have become obsolete. For example, the lab I work at has a machine that is older than anyone who works with it. But it does it's job and as swiftly and efficiently as it did when it was brand new. Replacing it would literally cost multiple millions and for what, so we can upgrade a $1 data port? Can you see how laughable that is? And this is a VERY common example of situations that exist all over the world. Motherboard makers aren't "throwing" in a serial port willy-nilly.
I don't have an issue with standards, but as you agreed, we're not always using the best standard and something it seems like certain standards only exists because there wasn't even a discussion about it and everyone followed Company X (which often is Intel).
This has little to nothing to do with Intel or any other big company. Industrial Standardization groups exist to make sure that big companies DON'T control everything, making sure that standards which are adopted have some logic and reason to them. And opinions about which standards are the best or most useful are as varied as the standards themselves.
I don't think I need to re-count the mini-ITX board ratio with SO-DIMMs compared to regular boards, maybe you misunderstood what I tried to say. As in, there's one mini-ITX boards with SO-DIMMs to every 25 of any other type of motherboards.
Oh, it really seems you do. That ratio of 25/1 was WAY too high. There are far fewer boards with SODIMM's than that 25 to 1 ratio would suggest.
The LS-120 was also much better than regular floppy drives, but way too expensive, just as ZIP drives, at least compared to regular floppy drives. Then again, back in those days computers were a lot more expensive than they are now as well...
Actually, I had both. The Zip drives, when connected by IDE, SCSI or even USB were MUCH faster than the LS-120. The JAZZ and Bernoulli drives before that, were also much faster than competing products from other companies. For a few years I stopped buying HDD's because JAZZ 1GB and then 2GB discs were fast[SCSI] and big enough for a complete OS installation, including software. Had a bunch of discs that had various OS installations on them. It was an amazing product. Ahh, good times.
I've honestly found nothing that says there's a throughput issue with SODIMMs for consumers. I can't find anything pointing this out.
How hard did you look? Try again..
Often, so SODIMMs are also double stacked, so density is still there. Again, you need the pins for ECC & Registered/Buffered ICs and their SMDs, but we don't get that anyway. I can't find anything about a performance penalty against SODIMM vs DIMM non-server.
It seems clear that you need to do a little more research on the subject. Everyone who understands how technology works knows that more data pathways=more data through-put at any given speed. This isn't just electronics principles at work, it's the laws of physics. But you are about to illustrate the point for me.
DDR4 DIMMs have 288 pins, DDR4 SODIMMs have 260 pins, and DDR3 DIMMs have 240 pins, DDR3 SODIMMs have 204 pins.
Yes, so DDR4's 288-260=28. That is about 10%. And that's about the performance difference between standard DIMM's and the SODIMM variant running at the same speed and timings. DDR3's 240-204=36. That's about 10% also. Shocking how those numbers correlate rather conveniently. Science is fun, isn't it?
Like others mentioned, it's ALREADY a standard.
Yes, a standard intended for mobile computing. It just so happens to fit compact micro-computing desktop needs as well, but at a performance loss.
This is purely one of those things that no one questions, so no one bothers and if done, it would be like "hmm, why wasn't this the norm before".
That's not true either, as evidenced by this discussion. The reason why is the aforementioned performance drop-off, so to anyone who actually understands the way the technology works, the question you posed answers itself.