Conventional wisdom says that powering smart bulbs on and off will shorten life span. I don’t personally know if that is true or not, but there are a number of authoritative sources that state that. So it’s not so much dimmer vs switch (i.e. partial voltage vs on-off), it’s the fact that power is being limited/cut to the lights at all.
If smart bulbs are controlled by a smart switch, then the control of the bulbs should be via scene or direct association in order to obtain maximum bulb life.