Is registry cleaning effective? [duplicate]

Most so called experts would say online that registry cleaning speeds up your computer. I just found a handful opinions that say otherwise i.e. Howtogeek article

Also there are some indirect answers here, but they are from like 4 years ago.

Would I be better off with not cleaning registry at all? Because benefits are dubious and the risk of messing it up is higher

A registry cleaner will not fix crashes or problems of any kind because it only removes entries that it knows have no effect.

While a registry cleaner will have a very slight effect on performance, it's generally too small to measure. The registry is a fairly efficient structure, so reducing its size slightly won't make accesses measurably faster. And the time to detect that a file does not exist is pretty small too, so removing entries that lead to non-existent files won't save much time either.

That said, I'm one of those guys who likes a clean and tidy system. I defragment my drives because I enjoy it and I run a registry cleaner because junk offends me on a personal level.

Not for performance. (You might shave a microsecond somewhere, but you've already wasted a million times that by clicking the Clean button.)

However, if done properly, it can resolve discrepancies in the system that confuse the user or other applications.

To give you a hypothetical example (I can't remember if this is exactly the sort of thing that can happen, but it's similar to the discrepancies I've seen happening and fixed), imagine uninstalling Photoshop and still seeing .PSD file types showing up as "Photoshop Document" but without any valid icon. This would indicate there are stale entries in the registry, where e.g. the description is present, but the file type handler is absent, and would leave the user wondering why the word Photoshop is still present even though the application has been already removed. Similar things can leave other applications confused too, e.g. the handler might be present but the program it refers to might have been uninstalled, and hence it might no longer be possible to open the file.

So yes, they might be "effective" in some cases, and a Properly Written cleaning tool Should Not cause problems. But in practice, I wouldn't highly recommend them unless you're willing to examine what the tool is actually doing. The potential to break something further is too much to risk for the possibility of removing a user-visible discrepancy unless the user knows and limits what the tool is doing.

Literaly the answer is NO and YES but carefully and only with good justification.

Oviously modifications or cleanup to the windows registry haves Advantages and Disadvantages.

Im personally against that Registry Cleanup Software which made a one touch registry clean task, without any noticeable warning, you always should keep in mind the scenario where it is mandatory to touch the registry.

Scenarios:

Malware/Virus Infection

Some viruses and malware, stores registry keys to reinforce the infection. you should use some anti malware software feature to remove that malicious keys from you registry and in that scenario the Registry modifications are justified.

Registry Damage/Registry Corruption:

If you experience Registry Corruption or Registry Damage you could use an especific tool to recover your lost registry keys from a previous backup.

There are only 2 scenarios only as example, but could be many more.

And be carefull using Registry Tweakers only because you was warned by an ad or by a mail or for amateur forum, it could be only a trick to infect your system, there are some Scareware just to made some scamm to good people.

Only using Registry Cleaner to remove unused keys or orphan registry keys maybe will Boost the Start-up cause registry will be smaller and will take less time to be loaded.