My answer would be no...there is no such thing as a "registry cleaner' or "optimizer" that can increase the efficiency of the system. That (and the following) are my opinions.
For those who were not Windows users back then...it should be pointed out that these types of programs first appeared when Windows users were using Windows 95 and Win 98. They came about, IMO, because the 1990s versions of Windows...had a number of users who were capable of being exploited by claims that a given product would solve the "mysteries" of Windows which many were experiencing. Lots of questions and situations existed...which now are mitigated by users who understand more than how to click on an icon. Users did not understand how files could become damaged...and how to mitigate the situtions which developed because of such. Users did not understand the need for tools like defragment and chkdsk...and there arose a whole arsenal of "tuneup" utilities for these users.
The least understood but most used had to be "Norton Utilities". After some years...it beame apparent that rather than solving problems, NU increased system problems by forcing the system into a very labored state (very onerous program in terms of system resources) and it's "registry cleaner" function (which no one understood) just might be removing entries that were needed by the system to function effectively.
Typical Scenario From 2002
But...users continued to buy NU and other/similar products...because they believed the hype and ignored the common sense questions which they should have been asking themselves.
The same mentality is still prevalent...among new users who seem to know little more than how to find/select icons on their systems...and the folly of "registry cleaners" continues because...it's easier to believe that something is valuable when you don't understand what it is that this something is supposed to be doing for you...or why you need it.
Many of these users...haven't even bothered to try to find out just what this "registry" is and why it might or might not need "cleaning" or "optimization". They make themselves available for exploitation and ignore the logical question of how installing these mystical "registry cleaners/optimizers" can prossibly provide any positive value, as opposed to unnecessarily employing system resources that could be used to provide a smoother, more efficient Windows install.
Since new users have increased dramatically over time...today we have more users who think that "registry cleaners/optmizers" are something to be values...as opposed to in fact being something to be avoided.
IMO, the people who think that "registry cleaners/optmizers" are a necessity for their systems...are probably also part of the large community of computer users who believe that malware is something that happens to "the other guy" and ignore user responsibilities for protecting and maintaining...their computer systems.
It's what I would call the "witch-doctor approach" to owning and using a computer.
The sad thing is that there is plenty of information existing for users who are willing to use Google and find out definitively just what the registry is...why it's important...and why "registry cleaners/optimizers" are as close to a scam as anything can get.