Since Luxor mint NFT with 3.94 MB on their block which has Ordinal ID/number 652[1], now current highest Ordinal ID/number is 6681[2]. While not all of them have transaction size >300KB or ~3.9MB, it's clear 1 sat/vB isn't enough to discourage people to mint BTC on main layer.
actually having hard consensus rules again that are set to, for instance: limit witness to 80 bytes is a solution
Why 80 bytes? I expect some multi-signature address which use P2SH or P2WSH would unable to spend their Bitcoin if this limit is enforced on protocol level.