What you prescribe is useful, and do-able, for some people who can maintain high focus while using their computer. FWIW, I do a variant of the same thing, and like you, I've been extremely careful, and fortunate, for over 25 years.
Most users lose focus at some point while computing. I've seen it happen SO many times, to co-workers, family members, friends. They forget for just a moment.
And it's like losing your situational awareness while flying a plane, or in combat. A few seconds of letting yourself get wrapped into a state of mind that's not 100% focused could cost you everything.
I applaud your care, and second your list of cautious instructions. But we have to recognize that not everybody can do it.