This is specifically why I call out the federated model as a nice-to-have, not a requirement. ActivityPub is way, way more demanding of CPU and transfer than a simple forum, and as a result it's extremely difficult to self-host at scale. You can easily service 10,000 daily active users on a VPS serving lean, statically-rendered forum pages.

Mastodon was not designed to be cheap to host

> Mastodon was not designed to be cheap to host

Is there a reason for this, though? Need to be able to iterate on features quickly? Maybe not being able to tackle various complexities with the total available resources? Or maybe federation is just inherently expensive?

Why couldn't we have an alternative written in a more performant language/runtime with maybe things like lower quality images/videos or something?

> Is there a reason for this, though?

Because performance was not a concern when it was designed - or it could be that it was designed for small communities, and therefore not possible to scale-up cheaply. One of the problem is the caching of pictures from the different instances connected (if I remember correctly) which makes the data storage requirements go up very fast