Let's start treating tech as the world treats everything else: Ignorance is not a justification
Sure, there's a midpoint where we would ideally want as many people to be able to use a technology as possible, which means making things easier, but we underestimate the capability of most users and dumb things down so far that those users not only believe that X technology is too hard but believe themselves to be too stupid to do anything that requires even the faintest amount of know-how.
I do think we've gone way too far in the direction of acting like everyone, except we archmages on HN, have the intelligence of toddlers and can't figure out anything for themselves. Everything becomes so easy, but at the tradeoff of everyone being dependent on the centralization.
The incentive has to be there, though. Convincing people to self-host is like telling them to eat more broccoli. Just because it's good for them doesn't mean they're going to do it, and companies of nearly any size certainly won't choose to make things hard on their users.
We would be much worse off. In order to survive, everyone would have to become a dabbler in everything and many would be unable to keep up at all. We would lose all of the efficiency gains of specialization.
So assuming we do not want everyone to have to learn a bit about medicine and law and engineering etc, why is computer knowledge different? Is a computer not merely a tool to accomplish a task? We don't expect people to learn to become a mechanic, let alone an automotive engineer, to be able to drive a car. We expect cars to be reasonably easy to drive and low maintenance, with occasional help from mechanics. Shouldn't we expect the same from computers?
We can be realistic about making hosting accessible, or you can bury your head in the sand with enthusiasts as AWS becomes the entire internet. It’s already pretty obvious which approach is winning.
People working in other sectors, maybe with a family when they come home, do not have that skill or luxury.
And speaking from experience, documentation is often greatly lacking. For example just today I had to thumb down a couple of google docs because it was riddled with inconsistencies and lacking crucial information. And that’s a company with near infinite money. And its like that for most software, with great docs an exception rather than a rule.
The number of people who can learn all of the skills that someone in the world considers essential is small. The number of people who can do all those things while having a job, kids, and a working partner is smaller still. The rest of us have to focus on a proper subset.
For me, every minute I waste learning how to configure my server is a minute I could have been playing Legos with my kids or riding my bike or sleeping.
But eventually they will be old enough to require an email address, so should I just let them use Gmail and stop worrying, or try to have something up and running until then? At least protect them from the data kraken until they can make their own informed decisions about that. But then I'm not just responsible for my email, but my whole family's email. What about 30 years down the road, when they long moved out? Am I still gonna sysadmin my family's self-hosting galore when they finally have kids on their own? Is it even still possible then? At least for mail it looks like when it's growing over my head I can just sign up with some mail provider (that hopefully values privacy) and let them handle that whole BS.
It might not even be worth it anymore at some point though, if basically everyone else you communicate with via mail is on Gmail. Then Google already has all my email as well.
An awareness campaign to go the extra mile in terms accessibility would be great (and that doesn’t mean dumbing down, the two seems to be equated sometimes)
But also at past companies there was never the idea that internal tools had to support accessibility features, as we give for granted that we would never hire people with some sort of disability and they are just users that stay at home, it's sad and upsetting, as a person who doesn't need any accessibility feature to operate now, I really feel sorry for others who do, and I hope that I will never need them, because like your situation with products at employers like control panels and similar is very sad
The best I managed to do is that my family's email addresses use a custom domain I manage so I am not locked into a single webmail provider. Occasionally I have to deal with some issue or delivery delays (especially for authentication emails) but it's orders of magnitude less effort than when I made the mistake of trying to run my own mailserver.
Being self-sufficient is a noble goal, but I think it's also helpful to be realistic about the costs in order to make the proper cost/benefit decisions.