No, it's not.
Personal experience.
RB25s2 is not stronger than s1. The nylon compressor wheel like to delaminate when leant on too hard.. had one in the workshop not so long ago with lots of bits of nylon missing of the wheel.
I recently sold my RB25s1 turbo, that thing spent a year getting abused at 12psi on my RB20 and another year getting abused at 12psi on my RB30 while also being a restriction, which meant the exhaust housing was getting super hot and the exhaust wheel still didn't fail.
RB25 Neo turbos have a slightly bigger exhaust housing.
I think it's pretty much luck of the draw, boost it over stock and it can fail sooner than if you didn't boost it.
That being said, I still prefer RB25s1 turbos and will advocate them over the later nylon wheeled units.