Then I guess you'll have to decide how important that card reader is to you. I will say the
Apple USB-C to SD card reader has worked flawlessly for me with my M1 MBA. So unless you are constantly using SD cards to the point where there's almost always one in the machine, then you may want to consider just keeping the machine and using the "dongle" instead for occasional use. I'm also not sure if it's truly the hardware or something that could be addressed by software.
A couple years ago, I discovered that neither of the 2 Thunderbolt ports on my 2012 27" iMac worked (hadn't needed to use them before that, so not sure if they were DOA or over time). However, everything else with the computer was fine.