big picture, i think Marvel is more interested in showing different timelines (different actors playing the same character) like Spiderverse, than to have evil 616 Loki in a goatee or something
since the minute men grabbed our Loki in time there was no Nexus event, so AS FAR AS WE'VE SEEN, there wouldn't be an opportunity to have a bad 616 Loki
to the particular question, i don't think you show how small Thanos is (with bauble infinity stones) and then try to conquer Thanos - bad Loki is probably after TVA power
*"616" was the designation on Loki's file - if they're staying consistent, that's 'our' timeline (the one we've been watching)
imma guess that it's going to be important to distinguish different timelines soon