Half true. It heavily depends on the indivdual board.is this true?
USB4 is offered by an ASM4242 controller via PCIe4.0x4, but it always seems to be linked to the CPU instead of the Chipset, so you lose 4 lanes of the CPU that have been used for an M.2-slot on almost all X670/B650-boards.
On X870E and X870 you always have a PCIe5.0x16 and a M.2 with PCIe5.0x4 from the CPU, same as with X670E and B650E. Any additional M.2 with PCIe5.0x4 now comes from reducing lanes of the x16 to x8. Many new board offer two additional M.2 by giving you that option, which was much rarer on X670/B650.
The rest should be the same as X670E and B650E, but you don't see any new board with more than 4xSATA (there were few like that with X670 already!) and most of the X870 only have one additional PCIe-slot and one M.2 from the Chipset. Since X870/B650(E) only has 8 lanes PCIe4.0 and 4 lanes PCIe3.0, which can be turned into SATA-Ports, but need at least two lanes for 2.5GbE and WiFi, you can't even have 4xSATA, one M.2 PCIe4.0x4 and one PCIe4.0x4-slot at the same time. For more, you need X870E/X670(E).
In my opinion it doesn't make much sense to have more than one NVMe-SSD linked to the chipset either way, since the connection between CPU and chipset is only PCIe4.0x4 as well.