When a few years back AMD motherboards where much cheaper than Intel motherboards, people didn't seem to have a problem with that. Because FPS counter and single thread performance off course.
Now everyone talks about motherboard pricing.
The same with thermals, power consumption, multithreading performance. When AMD had an advantage, over Nvidia or Intel, it was unimportant. When AMD had a disadvantage, it was the de facto deciding factor in choosing hardware.
That being said, Tom's Hardware had a very analytical article about, why AMD's motherboards could be more expensive than Intel's.
Why AMD’s Ryzen 7000 and Motherboards Cost So Damn Much | Tom's Hardware
More than what in that article is said, I also have a theory that, this time motherboard manufacturers are not willing to support a motherboard for 3-4 years for free. So I believe that AM5 motherboards integrate also a small TAX for that extra long time BIOS support. A motherboard manufacturer selling an LGA 1700 motherboard, know that will not have to add new architecture support for that LGA 1700 motherboard after 2023. On the other hand, the same manufacturer knows that the AM5 motherboard sold today, will need to get BIOS updates for at least until 2025. That much have a cost.