The nuke icon is dedicated for Beatmaps where the owner of the beatmap rejects to change unrankable issues and being contracted to admit them. So these maps are "restricted" to be rankable until the mapper decides to change its behavior and for the sake of beatmap to solve the issues.
On-Topic: Maps like TAG4 are
currently called as gimmick maps. They were some ideas about having a own Ranking category which is similar to the Approved one since maps like BlythE (Osuka) or Evanescent would belong in this category only. As well, TAG Maps went into this category (not only because of the score limit of 20 mil but also because of their difficulty). While Beatmaps like BlythE (Osuka) or
Fear Factory are gimmick maps since they play and build a lot in SB and skin elements, other beatmaps like Evanescent or TAG Maps are incredible hard and "actually" not intended to be ranked.
The point is: All these maps aren't bad, partly they're even good but would not fit into the Ranking section because they use uncommon mechanics which would manipulate the amount of pp (one of the reasons why TAG maps doesn't give them anymore). Of course there are also Beatmaps around which are something like art - so that means you're actually watching them instead to play them, common examples are The Big Black or Centipede.
Litte recommendation: https://osu.ppy.sh/b/583277 /runs However, the last two examples are fully unsuitable to play.
Default wrote:
[...]and the beatmaps would give no pp, but the scoreboards would still be there, just for fun. What do you think about it?
I get your point, that of course would be required to have them existant at all. The actual problem is to declare them as gimmick maps. What are the criterias for them? Is it worth calling them as gimmick? Do they just exaggerate with that what are they're supposed to be? It's a very very tough thing to have something solid for such maps.
Default wrote:
It would have a (way) less restrictive modding procces (things like timming and fixing broken stuff, nothing more)
I find common sense should still be fullfilled like the correct BPM/Offset and the safety what the Beatmap provides (no NSFW, gore, anything what's not suitable for children and general for humans). Another thing like experimenting with Offsets and to double/half the BPM could be done if well used.
Default wrote:
This category could include maps like TAG4 diffs, maps which are just too hard to be ranked, with notes in sliders, with an extremely low AR...
I find TAG Maps are examples of Beatmaps which never should've been ranked unless there is a option that these maps are Multiplayer-only. Because such maps are honestly bad to play alone (not how they are mapped, just to make sure you and other don't get me wrong).
As said, this idea is around for years but something like process hasn't really happened since now.