RX 6500 series has only 4-lanes PCIe, which is a serious 'bottleneck' even in PCIe 4.0 mode (it's twice less than of RX 6600 series and four times less than of RX 6700 series).
If CPU/motherboard this GPU will be used with supports PCIe version 3.0 only, then its transfer rate will be twice less (about 4 GB/s, instead of 8 GB/s). For comparison it's only twice more than transfer rate of AGP-8x (2 GB/s) that has become a history in the beginning of 2000-x years...
Looks like a lot of people out there are upset of AMD making them to completely upgrade their systems this way...
They buy this "pig in a poke", as always expecting no such surprises (many prefer AMD exactly because unlike Intel it never used to drain their clients' pockets this way), then face performance problems and trying to resolve them realize there are only 2 ways: replace this GPU to at least RX 6700, or replace CPU and/or motherboard and in some cases memory as well.
Though PCIe lanes count is a very important parameter that affects GPU performance in a significant extent, nevertheless it is not even clearly mentioned in official specifications web-page. So, looking at it some won't notice something is not alright there...
I just hope a decision to introduce a GPU series with downgraded PCIe port was forced, probably due to IC production crisis in the world, in order to reduce faulty ICs amount.