I think the issue so many take with development and a lack of progress, in this manga and similar ones, is that the mangaka will not just keep doing the same thing over and over and keep a consistent focus on the gag or cheesecake or fluff, but that they introduce plot and advancement elements only to then pull the rug out from under it and basically not use anything they actually introduce in any meaningful way. Like if you're never going to move the plot ever then don't pretend like you're going to. The irony is that many mangaka do it to prevent a manga from becoming stale but all it really does is serve to greatly focus the experience for readers that yes, nothing is going to happen.
I mean, if you don't care about that and click through pages until you get to a butt then that's completely fine. But it's kinda disingenuous to act surprised people dislike when a manga doesn't have any momentum and remains stagnant due to...well, reasons? Like if they really didn't care about moving anything forward or how that looks to people then there are plenty of manga that do this un-apologetically. But they know what they're doing when they fake us out with progress and reel back from it.