Yep. I'd say their legacy was "cemented" with ATYCLB. At that point, they did it all...a well respected debut, huge commercial success, wide spread critical phase, reinvention, experimentation, critical backlash, a loss in popularity and finally culminating in a massive critical and commercial comeback which crucially created a new generation of fans. Everything a band can do, they've done. Nothing that they've done since 2001, or will do, IMO is going to significantly impact their legacy one way or another, and certainly comments that they're "damaging" their legacy are absurd. Despite them doing their best, most crucial and memorable work prior to 2001, that "comeback" was critical, IMO, to how they are regarded today.
Had they just fizzled out after Pop, it might be a different story. They'd still be respected and fondly remembered, but not among the elite of the elite as they are now.