VFDs also fail about 2x to 2.5x as often as anything else in the system. In small commercial applications they often end up bypassed within a few years of installation of that equipment. They're also unusually good at catching fire due to the design requirements of the part.
Properly sized multistage A/C systems are a much better idea.
You do see drive failures, but they’re less common than they used to be, almost every drive my guys install is an ABB drive and they’re pretty reliable.
You are correct about soft-starters being a lot simpler and requiring less maintenance, as it’s more or less just another contactor inside a regular across-the-line starter with some extra control wiring to handle the extra contactor. Adding an inverter, rectifier, and solid state electronics does make the complexity much higher.
Properly sized multistage A/C systems are a much better idea.