No one's actually saying this though, it's all hypothetical.We don't know what the full story is, and it's a completely different situation. With Blaze, he had multiple years and two full world tours to grow into the role of Iron Maiden frontman. It's pretty clear that by mid-1998, it just wasn't a good fit live.
Yes, Nicko's playing is noticeably different this year, but since 2012 he's been bowing to the demands of Bruce and Adrian more in terms of tempo and playing things closer to the album speed. There could be another request from someone in the band to simplify some parts for whatever reason.
Or... maybe he's recovering from an injury or an illness of some kind. Remember all the talk about Bruce not running and jumping around as much in 2019? And then we learned in early 2021 he had been having serious hip issues to the point of needing a replacement in 2020. We have no idea what he's going through, and may never know. The differences in his playing may just disappear the further they get into the tour.
The point is... we don't know the full story, or how things will play out over the course of the tour. All of this calling for Nicko to step down based on a couple of early shows with a challenging setlist is way overblown, IMO.