Banishment is not inefficient. It’s a one and done kind of spell with respect to saves, something hold spells are not. And while the creature may be coming back in about 10 rounds, it usually gives you plenty of time to clear out any other creatures in the encounter, prep, and then concentrate power. We find holds to be not nearly as convenient.
I don't wanna derail the thread
too much, so only gonna post on this the one time, but...
Banishment takes something (unless it's extraplanar) and knocks them out of the fight for a minute (if they fail, otherwise it eats a slot for nothing). At the cost of a 4th level spell slot (so polymorph, conjure woodland beings, upcast spirit guardians aren't being used), and your concentration for a minute. As a 7th level caster, or higher.
Tasha's Hideous Laughter incapacitates a target for a minute with a first level slot and your concentration. Now, unlike some of the people in this thread, let me acknowledge the drawbacks upfront: yes, you get a save at the end of each turn, and yes, they wake up if they take damage. But if you want to knock one thing out of the fight you can do it way cheaper than with Banishment.
Hypnotic Pattern. A spell level lower, hits a bunch of stuff and knocks them out of the fight. I acknowledge that some things are immune to charm so this isn't always applicable, still a way better effect any time it applies.
Suggestion. DM dependent, but at
minimum you can probably use suggestion to remove a foe from the combat for an hour. I see some people treat this like hard mind control and the suggested creature should do everything you want (those people tend not to be welcome at my table because that's a really poor reading of the spell), but you don't need to treat it anywhere close to that for it to function better than Banishment.
Web. Can't charm the creatures? Web them. One might make a save in a group, but they all probably won't.
So the main benefits of Banishment once you stop targeting something extraplanar is they don't get to repeat the save, and charisma is a good save to target. That's it. But does that make it worth a higher slot than all of the above? It's only better than the above if something is alone (so you can't benefit from web or hypnotic pattern to the same degree), and is immune to charm effects, and isn't a humanoid so you can't hold person it. If it's a humanoid, hold person is way better. Paralyzed generally means "dead real soon."
And 10 rounds? How many fights genuinely go that long? I have seen some, but those are really big boss battles where you'll probably want to cast a better spell to use your concentration, one that impacts multiple targets, or swings the fight more than just removing one thing that doesn't have a legendary resistance. Banishment isn't so bad it's unusable, but it's hardly a spell I'd say is so stronk that making it even harder to pass (at the cost of your reaction and a 1st level spell slot, mind) is breaking
anything.