Yeah. On a 20" wheel there's nothing too difficult or complicated up to an 11-46T cogset with a medium cage GS RD provided the tires are not ultra thin and you finesse the chain length. Greater than 46T is where you go into the questionable, risible results, as has been amply and sadly demonstrated on this channel. You'll know the thread.

I myself have been trying to push this envelope since 2016 when the now common wide range cogsets were either unavailable or way too expensive. Here's me with 11-36T and Zee as late as eight years ago



In 2018 I made the jump to 11-42T on 20" and to 11-36T on 16" (ISO305) so I've been at this game a while. I guffaw when Johnny-come-latelys tell me what is and what is not possible.