That’s what we have a blocksize limit for. Even if every block was 4MB (which it isn’t), it doesn’t matter. That’s still nothing.
Discussion
A more worrying issue would be the UTXO count becoming too big. That's peoples concerns with stamps as far as I can tell.
Yes, maybe now solutions like utreexo might be more feasible to adopt.
The problem with UTXO is that it is usually in RAM. Here in this podcast Tadge Dryja talks about it a bit.