Thanos doing apparently little else than blow up planets as an ineffectual temporary band-aid measure (seemingly blown up by Black Panther), while Doom schemes and preps w/ Molecule Man, reverse-maps the entire Multiverse via the Mapmaker network, and prepares to confront the ultimate source behind the Incursions.
Yeah... sometimes you have to actually look and see what's actually going on rather than deal in knee-jerk reactions as truth.
Thanos with prep became GOD with the Infinity Gauntlet, Doom with prep became GOD by claiming The Beyonders power. Personally, Id say this is a damn close match, with each of them proving they can be the Ultimate Power In The Universe with prep time (and noticeably less than 2 months, at that).
IIRC Doom got the Beyonders powers because the Beyonder subconsiously gave them to him, not because Doom jacked them against his will.
The entire (insert character here) getting omnipotence shtick is a silly outlier anyway, Doom (and Thanos for that matter) shouldn't have their entire prep careers defined by some abnormally high showing.
I guess I can give Thanos a pass since he is a cosmic level character and has access to tech and knowledge that would make Doom, Reed and most Earth based geniuses in both Marvel and DC flabbergasted.
Well, in addition to stealing the Beyonders powers, he did so with Galactus, and twice with Surfer, so hes well versed in stealing abilities of Cosmic Beings / beings much stronger than himself. Saying its OK for Thanos to reach omnipotence, and not Doom because hes just a man, doesnt fly with me really.
Hey, Id probably give the majority wins here to Thanos as well, but anyone who things Thanos would Crush Doom is a fight such as this has no idea what Doom with 2 months of prep is truly capable of.