Your comment seems to infer that you're unable to empathize with people who might think/understand differently than you. It also seems to negate that you avail of other services/non-self-controlled processes without worrying about the threat models, there.

Just hand-waiving with a "Why don't people just do 'x'?" is ironic - in the sense of "Why do you do your own medical care?" or "Why don't you grow your own food and slaughter your own animals?" or "Why don't you manufacture your own phone, it's operating system - oh, and the cellular tower closest to you?".

Threat models exist, _everywhere_, and it's impossible for someone to build all of the pieces, themselves, to prevent all threat models at every possible avenue/point.

In other words, at a non-arbitrary point, doing _everything_ yourself is untenable and that's precisely why services in society exist, today (that and ease of access, use, required foreknowledge, and - most notably - cost).

And it doesn't anonymize you that well. When you post a message that draws the attention of law enforcement, the IP will lead them to a VPN provider that hopefully doesn't keep any logs.

But if it leads them to a specific server, the hosting provider will disclose your account and payment data, since it is linked to your private server. Unless they accept fully pseudonymous accounts and let you pay for your VPS in cash, Monero or tumbled Bitcoins, finding you is much easier now.

Not to mention the other stuff the VPN providers give you as standard which you'd have to implement and maintain yourself.

Compared to the rest of the world, the number of people who even know what a VPS is is microscopically small.

And even those that do, the number of them with the time, desire, or skill, to do as you suggest, is even smaller.

I myself was into this sort of thing just 10 years ago. Now, as I start looking at hitting the big 6-0 in just a few years time, I’m already working on divesting myself of all this complexity,