I think you are mixing the big companies monopoly with Open Source.

very dificult to self host email

It is not (example: https://mailcow.email/), the difficult is to keep it safe, updated and pay the hosting, but there are alternatives of email hosting like https://posteo.de, so I would say you just didn't search for any alternative.

before we had personal websites

You can still self-host your own website, if not, you can find a provider or use alternatives like https://gohugo.io/, it's full of it.

community forums then reddit came and take over the forums making profit of off it

You can still use Lemmy and forums... I never used Reddit, so I don't see what's so good about it, a part of some posts that has some good info as any other forum or website that I got into. I don't see how this damages open source or where is the issue with the open source.

The real problem is the people ignorance, they are still using the big tech apps that have more marketing that other ethical apps. But there is nothing wrong with FOSS here, big tech uses this mass control as government does too to control civilians feelings and thoughts.