Disappearing Clef

It's not overkill at all - it's absolutely how music is normally published. I know there were some infamous college-student-produced fakebooks back in the 70's that omitted clefs regularly even for pieces that changed clef, but it's not considered good practice at all. Those college students did it because they didn't have the advantage of notation software to calculate correct spacing - omitting clefs and keys allowed them to just divide the staff into four equal measures before adding notes, which simplified the process when doing things by hand. But it's unnecessary and unhelpful today. Especially, as noted, in music with clef changes. It's a recipe for confusion, as musicians are likely to not notice the clef change. And if there are repeats (including DC or DS), good luck guessing which clef is in effect when jumping back if you can't just scan back to the beginning of the line.

If the idea is to show a bass line up front as an intro then switch to the melody alone, the better way to do this is to have two staves - treble and bass - for the intro, then switch to treble alone after that (using Format / Style / Hide empty staves within systems). And actually, that approach works even if you wish to not show the treble for the intro.

Anyhow, if you still wish to not show the clefs, you could add a section break after the intro, which will force the next system to be treated more like the start of a new piece, including clef etc. You would probably want to disable the other options in the section break properties so it doesn't restart measure number, indent, etc.