I have historically regarded registry cleaners as snake-oil cures for all your ills. However.......
A couple of years back a friend (who is no novice) recommended Glary Registry Repair. I was, of course, skeptical, but tried it out on a few boggy machines. In some, but not all, cases, I noticed improvement.

I frequently get called upon to "clean up" a machine that is "so slow". My cleanup procedure now includes uninstalling unnecessary and undesireable programs, removing unneccessary startup items, a quick scan with Malwarebytes, disc cleanup with CCleaner and registry cleanup with Glary. I've never had it misbehave (in more than 100 uses). While it may or may not provide some benefit, at least the scan is quick and I haven't seen a downside. The client generally reports a performance improvement, but it may be the placebo effect or due to the other steps I perform.

I have not tried CCleaner's registry tool, may have to give it a look.

Primum non nocere