I understand our EV Blazers all came with 21 inch wheels-and "self-sealing" tires.
I've never had self-sealing tires before, so I don't know anything about them.

 

2LT models come with 19" tires. My 2LT Blazer EV is running 255/60R19
I'm hoping to be able to run 18" tires for winter (255/65R18).

 

I think it's possible to use run flats on an EV. But they could affect the ride quality and the noise when driving. Plus they could wear out differently than standard tires.

 

If you mean self sealing tires then yes. BoltEVs all come with Mich Energy Savers that are self sealing tires.