At what point does bandwidth significantly impact decentralization?

I'm sure this has been covered, but a quick search didn't really turn up much. I know pruning can be used to minimize storage requirements, but at what point does bandwidth matter? I know some other chains have requirements of 1Gbit or more, which must have a huge centralizing effect.

I assume there is a threshold for block sizes that render lower bandwidth participants functionally impotent. I assume 32MB blocks are fine but 1GB blocks coming in continuously would be very centralizing.

Throttling and caps are a reality for many internet users too. But maybe that wouldn't be as decentralizing if people could run nodes intermittently.

Again, sorry I know this stuff is pretty basic for you guys.