Nope, loads of people made that mistake..... it's your maximum PL that's limited as a bug player. So in a 1999 point game you are allowed a maximum of PL2.
Doesn't say you can only be PL2 it says maximum PL2. So you can still go PL1.
Marauder platoons are always PL2
If the bugs were limited to one PL per points cost band, it would basically hand the initiative to the MI in every game as in every case you could go one PL lower and then buy a SICON LT who allows access to the higher PL equipment.
E.g. 3000 point game...... go PL2 as the bugs would have to be PL3, this isn't the case, they can actually pick PL 1 or 2 instead.
Without this the MI would pick up a serious tactical advantage as they could always have a lower PL with no guesswork, giving them the advantage in setup, picking first or second and starting all of their models on 'ready' status (another little rule lots of people overlook..... the lower PL force can start the game readied, this can be lethal e.g. pathfinders, jump in 12" and open up with everything, the bugs can't react as pathfinders don't trigger in turn one, the pathfinders can then shoot again or ready, so they can jump out again in the bug turn).