And it was largely correct. 99% of viruses were for PCs. And had you asked anyone at Apple “can Macs get a virus” they would have said yes.You and me know that a PC virus cannot affect a Mac (and the opposite), but the message sent to non-tech people was different; it was "no virus here".
I’m glad you brought up non-tech people though, because what you are advocating for is significantly worse for the vast majority of non-technical users! Moving apps off the store will result in many falling for spoofs of the Facebook, Epic, Spotify etc. websites that leads them to download malware and/or spyware on their devices. Which is bad for Apple, bad for its customers.
There’s a reason Android is significantly worse from a security perspective. Users who side load are 80% more likely to have viruses running on their phones! Apple is absolutely correct in preventing it.