Tasha's says only creatures up to CR 1/2 are eligible. Obviously you can do whatever you want for your own table, but at that point you're not using it as intended. If you were to use it with higher CR creatures, at a minimum, I would apply a level adjustment.
Yes...yes it does...FOR NPCs....
However, does it say that same thing for PCs?
You COULD read it that way, but then it is contradicting the rules that came before it that allow them to play certain "monster" races that have only been rated at a CR higher than 1/2 (for example, Duergar) if taken in that literal interpretation.
From what I've read, it doesn't say much at all about PC's who take these Sidekick classes as PC classes at all. IN fact, it's only about a few lines, which make the rules EXTREMELY vague regarding them.
This could allow a DM to be extra restrictive (in which case, as a player I'd revolt when they let one player take a race but disallow it to another against the explicit rules...)
Or, a more liberal reading which would allow a LOT of latitude to players.
Of course, regardless of that, still have NOT read a convincing argument in this thread of why Sidekicks get a +2 better to hit than other PC classes.
The only somewhat arguments are that PC's get some things a level earlier (well...the Fighters at least...some of the other martial archetypes are still not justified in comparison by a long mile) which could be an answer...but not really all THAT weakening to the sidekicks unless you STOP your campaign on the earlier level...
OR...Feats.
Now, with Feats, those are optional. They are used to REPLACE as an option, the ASI's each class gets. If the classes get to the option to replace ASI's by choosing a feat, by that same rule, a PC playing a sidekick class should as well...which to me renders that idea that Feats give other PC classes an upperhand a moot point.
I don't see a single rule that says that if a Player takes a sidekick as a class they are then excluded from the other optional rules that every other Player can use.
