Robust security does not mean "system lockdown." However, that said, with "system lockdown" 100% trouble-free usability is possible. Millions upon millions of endpoints across the globe have no issues with "system lockdown."
Somewhere over the past decades morons have perpetrated the propaganda (or agenda) that making any system very secure means that it is inconvenient or unusable. Within minutes I can craft a fully locked down system that only causes an issue once every 6 months or so - and the issue can be fixed within a few minutes or less. So there is absolutely no argument based upon any real-world evidence that it is inconvenient nor unusable.
A person's security is dependent upon the software and configuration of their localhost at about the 2 to 3% level. The remaining balance of security, 97 to 98%, lies elsewhere. It does not make one jot of difference what AV or security configuration that most any untargeted user decides to adopt.
At one time MT was a place that was serious about security, with a lot less emphasis upon security software, but then people turned it into a circus of pointless do-over discussions about "What is best AV?" and "Did you see latest AV Test Lab results?" And it became overrun with highly misleading YouTube tester videos, nefarious agendas, and evolved into cheap security theatre tabloid dramas. Well, it's social media and I guess at this late stage there's no separating the two.
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