I'm no great fan of Hitler or Napoleon, I consider them both to be foreign conquerors and comparably bad figures. But, you're right, I'm sure it will be fashionable for some to become fans of Hitler, just as it has become fashionable to be a fan of Napoleon. But speaking of the the Lithuanians, they seized the alliances they could, having just recently been occupied by the USSR I would expect them to expend their national energy against the USSR, not against the USSR's enemy, Germany. The enemy of my enemy is, after all, my friend, at least so long as we have a common enemy.Hmm, the problem that after WWII all these collaborators would have been exterminated, anyway, though they surely kept better prospects in their minds. Also, Hitler considered Lithuanians as untermench in difference with Estonians or Latvians who had no infamous connection to Poles in his eyes due to Polish-Lithuanian Commonwealth. That is why Lithuanian Waffen-SS was organized only in 1943 when Germans lacked manpower and when all Lithuanian Jews (190 000) were already killed.
This topic is solely about Lithuanian Waffen-SS, but since you got astray with "all Eastern Europeans fighting against evil empire USSR", I have to remind that a week or so ago a newly-elected president of Ukrain decided to whitewash crimes of Ukrainian Rebellious Army who were butchering everyone in the West of Ukraine. A century away, and Hitler will be glorified in West just like Napoleon is today.