This isn't entirely true. There is still a fixed max block size; it is just that some bytes are counted as "bigger" than others. In particular, the maximum block weight is currently 4MB. However, most bytes count as if they were 4 bytes; which returns us to an effective blocksize of 1MB. However, bytes that are part of SegWit's witness area only count as 1 byte.

This leaves a hard upper bound of 4MB block size, with a "typical" size of ~2.3MB if everyone uses SegWit.

While technically true that the block size cap has a hard limit of 4MB, which would be a block consisting of one transaction with only inputs, a 4MB transaction isn't valid for other reasons.

So it's not meaningful to talk about a fixed block cap anymore. Perhaps it is better to talk about "typical" block sizes the way you do.

What's important is that the 1MB limit is history, unless you have to make legacy transactions for some reason.