As much as it pains me to say it, it's true. I use predominantly open source software on all my computers with some small exceptions. I used to rely on some cloud services because of the convenience and nothing else. But leaks started becoming way too common and what I can say about all places that I've worked at, data is handled really badly. If you pair that with some OSINT skills, you can learn pretty much anything about anyone from a single leak. So over the past few years I've been slowly cutting down my dependency on cloud services. Nextcloud was the first big step, a zfs pool for backups, a few custom protocols for alerting and kill switches and that's it.

On paper this sounds really good but there's a lot of overhead when it comes to maintenance. "Yeah, it's just one more docker-compose.yml, big whoop"(yes kubernetes is pointless overkill if you are the sole user). I've said that too many times and it's not true cause it only takes one small thing that you overlooked and you have to spend a day or two to put everything back up together.

Another thing worth mentioning is that open source can be a good alternative but open source does not mean free or cheap. For instance, I've gotten really into drones and radio communications lately. Take hackrf and the baby brother that is flipper zero - they are both completely open source but neither of them is cheap. In fact, they are really expensive - they are effectively open source ASIC's. I'm willing to bet that north of 80% of the cost is down to the software and not the hardware - because polishing a piece of software to the point where you can pick up a product and use it without effort or a steep learning curve, involves a ton of work on behalf of developers and UX/I people.

And you can't really cut off all big tech - open source phones are BAD, you don't really have a good alternative to google maps and waze, you still heavily rely on search engines and a few dozen services if you start digging deeper. There are also a number of services which do not have an even half-decent open source alternative. Also not everyone has the skills to set up and run these things.

I think the big case in favor of self-hosting whatever you can is that while open source is far from immune to leaks, if it resides in your private network(which it should) without access to the rest of the world, those holes will eventually be patched and you can take action in the meantime - stop the service, block a few ports, etc. The odds of you personally getting affected are pretty low. Now if a leak happens in big tech, there's nothing you can do about it and by the time you learn about it, it's often too late. Honestly, this is the number one reason I'm doing this to myself.