While I agree that certain state sponsored actors and private interest groups are most definitely involved in discourse manipulation on reddit, Lemmy simply isn’t big enough for this yet.
If we go by the numbers stated in the original post, the whole of Lemmy has less than 500k users at this point, whom are overwhelmingly <40 years old tech affine early adopter nerds from the United States and Western Europe.
Too insignificant to spend resources on, and also largely sceptical of corporate interests and authoritarian governments (except the tankies of course); so by default critical of the two top potential manipulators.
I just yesterday saw a post how disabling downvotes for an instance that still acts as part of the greater fediverse causes issues and unfair advantages with posts being created there that can achieve a high score very easily, even on accident.
I would expect Lemmy to rework that function to avoid these issues so that up- and downvotes are either mandatory or can only be disabled together. I would not recommend trying to find an instance based on if they practice this most likely not here to stay functionality.