I did not sense a lot of improvement for registry cleaners, so I stopped using them.
For disk cleaners, I saw some savings for drive space, but also had problems with some browsers, so I decided to just rely on storage sense, and from there get more or larger drives.
For real-time optimization, I think the system no longer slowed down when apps misbehaved, but didn't speed up as much, and when more apps stopped misbehaving after they were updated, stopped using them as well.
For defragmenting issues, using an SSD is useful, but for some weird reason the system tends to be more snappy after I run the built-in app manually (e.g., trims the SSD and defrags all drives, and by default works only on small files), and it tends not to cope with some systems that are used for a lot of activity, e.g., play games, run apps, copy, more, or modify large numbers of small and large files across the same and various drives, install and uninstall apps, etc., so I'm trying various third-party programs, including those that don't defrag but instead do so on the fly.
For software updaters, I'm currently using Patch My PC, but for systems where there's a small SSD and some apps have to be installed in another drive, I can't use the automate option because by default some new software versions are installed in the boot drive.