> Why reject switch 1 accessories though?

Because the Switch 2 is a different machine. Games being backwards compatible (via emulation) doesn't mean the hardware is (or has to be) backwards compatible. Different display chips, different display protocols, etc.

People made all kinds of claims about how the Switch 1 wasn't USB Type-C compliant when it was discovered that the Nyko dock kept frying the power management IC in the first Switch console. I think a lot of that false communal knowledge has carried forth to the Switch 2, unfortunately.