EMI must be a solved problem because I see color LCDs parked on the front of every other category of test measurement equipment sold in the past decade or so. Every other measurement tool on my bench is using one, meaning scopes, spectrum analyzers, VNAs, power supplies, bench DMMs, etc etc etc.
For daylight use, my cell phone is perfectly readable in full daylight, and yours probably is too. That industry has driven display technology to this point and we’re all the beneficiaries of the panels they’ve developed.
In terms of UI, color brings an extra dimension to your eyesight and, used effectively, can convey a world a meaning that you won't get from a 7 digit display. Again, every other instrument I have on my bench (and most handheld ones) makes use of color to indicate all manner of situations. Wouldn't it be great if I could set a pass/fail boundary on my DMM, hook it into the DUT, and get a clear green/red indication if the reading is in range?
I know existing meters can last years on a single cell if used sparingly, but my workflow already includes the notion of a charger, my bench and my drawers have all the DC I need, and I already expect to have to occasionally recharge a device. If the device can make it through a work day for me, then that's enough battery. The same applies to my wall of cordless tools. I need an angle grinder to last me as long as my job takes, then I have no problem dropping the battery back onto the charger. This is an extremely common workflow in industry today and it won't be unfamiliar to most.
I appreciate that you have been using a certain instrument a certain way for many decades, but I don't think it necessarily follows that it simply MUST be that way forever. Fluke seems to think it's a desirable feature, but only on their highest end models. UI/UX engineers are a thing, and they haven't been sitting still. Some of us are more ready to embrace new technologies than others, and that's fine, as I suspect you'll have several decades yet of 7 digit displays available in the future. Me, I'm looking for something a little more thoughtfully designed and which makes effective use of modern technology. Better still if it was inexpensive and also performed well but... that might be a while coming yet.