The release date of the last explorer firmware is lagging drastically behind the last micropython version. Is it ok to flash the explorer with a bog-standard micropython uf2?
what would I lose?
Yes you can do that. You will lose all of the Pimoroni libraries and any functionality that came with them though. If you hunt around for stand alone libraries you can likely restore most if not all of that. It just ends up being a lot of work and effort, and a lot of code changes etc.