There’s no similar location on a drop-bar bike that doesn’t get in the way, particularly on my friend Gee’s bike with narrow bars.
With a display handlebar adapter in hand, this seemed less awful than anything else I had in mind:
That’s the front view, so it’s on the right side in front of the handlebar. I think it’s usable with either a thumb or fingertips from a hand on the top of the bar. The handlebar lacks tape, as mounting the brake sensors poses a challenge.
The view from the rear isn’t too revealing:
Not too unsightly, but definitely not a standard setup!