Hello Yalçın,
I am Jaspreet Singh.
- Most of the "your drivers are out of date" messages are false lures for making you download the programs
- sfc/scannow works for the purpose it is designed for. It is not a sure fix for everything. Some programs when uninstall will leave residual files which can be manually removed or in this case a cleaner program can be used.
- No no programs is requried to clear RAM in the way these apps do. They force close apps which are then initiated again by windows thus consuming valuable CPU resource. Windows is intelligent enough to hibernate apps that are not required consistently thus saving RAM but keeping the app so that its startup time is reduced.
- Windows default security is enough for day to day usage of system. If you suspect a malware Microsoft provides an upto date downloadable scanner for scan from here : https://learn.microsoft.com/en-us/microsoft-365...
- No You donot need optimizer apps. Keeping a proper maintenance schedule in the system as well as ensuring your system remains up to date is the best thing that can be done.
In my personal experience these apps do more harm than good.