The problems you say, connection/power downtime are the biggest ones. And they're frustrating, but not near as frustrating as things you paid for going missing, forever.
My point though is, if we can get workstations out of the box ready, we can get home servers out of the box ready. The software already exists, the hardware already exists. The problem is not that people don't want it, that they're lazy, that the tools don't exist, the problem is that mobile devices are deliberately built to herd people to these services. Once they're hooked they're hooked. They're fundamentally disempowering.
With the modern service oriented way of listening to music and watching TV, you risk losing what you purchased, you're manipulated by algorithms, you're trapped in the net of a service provider. Is that really less stressful than pulling out a CD and putting it in a CD player?
Digital media is better than cassettes. But the service oriented way companies expect us to do it now is not better. We really hit peak digital media with mp3 playing software on our smartphones. Everything since has just made the experience worse.
Yes self-hosting is a PITA. Yes things will go down. Yes it takes time to learn.
But owning the means of your production? Priceless.
We need to stop teaching people to be cyber-peasants, sharecropping a land they'll never own.
I self-host a lot, including a smart home setup that is not reliant on the cloud, but in the end looking back how much time I've sunk into this and how often it's down due to _my_ mistakes I don't really think it was worth it.
We should be encouraging self-hosting for those with the risk-tolerance to do so
Then you realize you need to access this setup while away from your home. You add port forwarding.
You run an audit to check if the system is secure enough so script-kiddies with a port scanner are not able to access your 'cloud'.
Then you realize your router is not so reliable. You add a watchdog which will reboot it once the connection becomes unstable.
Then there is a power outage. And if before you could just access all data using 4G on your phone, now you cannot. You add UPS to all critical parts of your home network infrastructure.
...
And it goes on and on. It is doable, but doing it well requires a lot of time, planning and resources. It's hardly feasible not only for a lay person but for 'power users' as well.