Why is Telekinesis Still Missing?

I'm talking high level, sustainable, able to target both objects and creatures, telekinetic spell.

I expected they would bring back Telekinesis in SoM as a high lvl spell and i am a bit saddened they didnt, thou i must say that with forcefull hand and gravitational pull (and others, but i like these) togheter with telek maneuvre and even things like gust of wind, i CAN get pretty cose to my concept.

I suspect that high lvl Telek would just be a bit too much versatile considering how spells are in general more specialized then in older editions, but wouldn't be possible to balanced it making it 9th or maybe better 10th lvl? Maybe even slapping an Incap trait if needed?

You've answered your own question, at least partly.

Spells that don't have specific discreet effects are nigh impossible to actually balance. Just answering the question of which spell level it should be is difficult because you can't know what the spell is even capable of if you make it as open-ended as telekinesis used to be.

And if you do make the spell and make it balanced, you run into the other reason why this kind of spell gets split up into numerous different spells with discreet effects; word count. Just like if there was only 1 polymorph self spell like there was way back when that covered all the things you can do with the various battle form spells there currently are, a single do-it-all telekinesis spell would either end up taking hundreds of words to explain the ins and outs and limitations.

Lastly, the issue that arises if you make the spell 9th or 10th level or put the incapacitation trait on it; by the time you get it you'd already have all those other spells which do the same things, and you're basically just creating a spell which can do numerous lesser effects over time... and sitting it next to massively impressive discreet effects that other 9th or 10th level spells have, so it's going to come out looking either not worth doing or unfairly potent depending on your point of view. Basically, compare getting to use the effect of any spell which currently says 'telekinetic' in it's name and a few others which could easily be the function of such a spell to implosion and each effect you can manage seems less potent, but then compare to how alter reality, miracle, primal phenomenon, and wish function and suddenly getting to repeatedly duplicate a lesser telekinetic spell or get to do more than one over the duration seems actually more potent.

So really, you could even say that the spell you're looking for already exists. It's just called wish instead of telekinesis, and it's very unlikely that there'll be an official option otherwise.

Yeah Wish is always a bit DM fiat if you dont replicate an exact spell, but i guess it would not be particularly controversial to design my own spell and get GM approval only to use it with Wish, i had not thought of that.
Still i do miss the old Telekinesis, oh well at least as i said the wide range of micro-Telekinesis does it's job pretty decently