I have a 6.5 digit meter because I want the precision, even though the accuracy of a 4.5 digit meter would be fine for me. You can use a 6.5 digit meter to measure small scale drift trends, and even when well outside of calibration, it can happily demonstrate that down to at least 5.5 digits or so accurately. That said, since my measurement requirements don't require 6.5 digits of accuracy, letting it drift and be out of cal for a decade or two will still likely be within 5.5 digit meter accuracy spec, which still exceeds my requirements, but will show me all of the fine detail of the nicer meter.
I can use my 6.5 digit meter to measure the tempco of a thick film resistor accurately at room temperature - just a few degrees of fluctuation, and that is a useful/fascinating measurement to me that would be tough with a 5.5 digit or less meter. I don't particularly mind if the resistor I'm measuring starts at 101.256k Ohms or 101.254k Ohms (for example), so the calibrated accuracy spec far exceeds my requirements and I trust enough in the architecture, component choice, and testing done by the manufacturer to not be dramatically out of calibration for no reason even well beyond the calibration period.
Maybe others don't have the same trust or do demand accuracy or traceability, and it's their choice to make, but for my use-case, a meter that's over-specified for my requirements but is out of cal shows me fine detail lesser meters can't, and is very accurate, even if it's out of its specification. Then if I get my hands on a reference that's been checked against a real standard, or a different 6.5 digit meter in passing or something similar, I can use that as a transfer standard to check my instrument out and verify that at the level of detail I can't otherwise verify on my own, it at least agrees with other instruments. As I've said, It's not the approach for every application or every person, but I think it suits a lot of use cases well. A calibrated instrument does have some extra value, but I don't think it's an inherent requirement for a purchase of a high resolution meter for most people/situations.