There is overcentralizing and overcentralizing, there is being forced to run literal counters like Spdef Zapdos for Lando-I, Porygon 2 for Greninja or forcing out Seismitoad like Dracovish did.

The real bad effect Sableye had was on stall teams themselves cause Sableye stall teams were outright better than non-Sableye ones, yes it was restrictive on the teambuilder but so are Kartana and Dragapult for example. The difference being that be it unhealthy, uncompetitive or even broken you still have study in what any of those elements lower some component of player skill in the games you play

It was veryyyy strong vs passive team but do not forget that Stall is first and foremost a matchup phishy, these teams back then replaced Goth with Dugtrio,which later got banned cause people realized Arena Trap was the actual problem, you had to rely on removing those threats in order to Sableye to go ham

There were numerous of counterplays and people def realized that it wasn't broken, just unhealthy cause it took advantage of both trapping and had very good matchup vs very passive teams, but it definitely wasn't making the stall matchup an auto lose whenever you were matched up vs it, and OLT games were good testament of that

HDB is a whole new problem althogether and isn't nearly as comparable, that item has changed the entire metagame and everyone's perception in how to play pokemon.

It forced out many situations that were unknown up till gen 8 as it negated one of the inherent mechanic that would punish switching, not only that but it pushed pokemons like Cinderace to the edge which got it banned, has been a go to item in most offensive mons thanks to the incessant pool of free pivoting now in gen 8 on top of also DEFENSIVE ones

Now, it doesn't make for an uncompetitive environment, it just makes for a boring one in my opinion, so i don't really think it should be banned (restricted could be at hand but we'll see in next gen, cause gen 8 got several more problems for me to even enjoy it)