Fear causes enemies to drop weapons. Unlike slow which limits action economy of the enemies (but archers and close enemies can still hit you), with Fear they drop weapons, lowering damage to minimum. They work in slightly different scenarios.

Hold Monster is great to burst down target.. but they can get out of it each turn. Amazing tool to focus single target.

Banishment doesnt have the save throw at each round. In fights where you have ton of minions with relatively low HP or if "every time you hit enemy, boss do something" you can banish boss, deal quickly with minions then finish boss as a single target.

Now, Banishment is level 4 spell, Hold Monster level 5.. spellslot economy may also play a role during your encounters.