Use #!/usr/bin/env bash instead of #!/bin/bash.
The former searches the user's PATH to find the bash binary.
The latter assumes it is always installed to /bin/ which can cause issues.
But, in all seriousness, you're right - you're making a trade. The question is which side of the trade is more portable. I use NixOS which doesn't have bash in /bin. So, I've had to ask people on my team to replace the hashbang. The /usr/bin/env hashbang has yet to fail on any machine so, anecdotally, it seems more portable.
This isn't me ranting against systems with new ideas about file system layout, this is just me being pragmatic: When it works on all my work-, private- and production-machines, I see no reason to run an extra binary in front of all my shellscripts.
If something works for X% of people and a trivial change makes it work for Y% of people (Y > X) then I advocate for making that trivial change.