How do you all pop out and remount rear wheel so easily with UPRIGHT bike. I can only do it upside down :(

I've gotten very good at fixing flats, dealing with chain issues while out and about. Its a comforting skillset to have being that im still pretty new to this hobby.

However theres one thing that bugs that **** out of me: I cannot for the life of me remove/remount the rear wheel while holding the bike upright.

Yet on YT i see bikers slipping it in and out in literally SECONDS.

I have to flip the bike upside down but once its that way I can remove/remount the rear very fast. Removal takes me about 10-15 sec and putting it back on about 30 sec.

Trying the same upright - not happening. I'm doing all the steps, chain on smallest rear sprocket, pushing derailleur arm forward but the dang wheel just wont disengage the chain.

Any tips gratefully received.