I mean.... if you don't consider the overusage of pex, Tapus "least restrictive," I've found that SM/USUM is quite stale. I actually like last gen's meta more, even if I like this generation's tweaks (apart from no-levitate gengar).
Still waiting for a much-needed knock off nerf.
People need to stop treating the tapus as a group and tart remembering that they're individual mon wit very different uses. Not a single one of them is in the A+ or S rank for viability so while they're in A rank, there's still quite a few Pokemon more viable and likely more prevalent overall as a result. So we're talking about four individual Pokemon who are all good but none are centralising.
It's less restrictive because of the sheer number of OU viable mon, strategies, sets etc etc. The presence of four very different powerful mon who all just happen to be Tapus doesn't hurt that.