I'd say as 'Dementhor' there ought to be a way to control exactly what is sent to the browser.
And like 'DiskDoctor' says it should be possible to setup a proxy.
I used an old browser by writing a perl proxy. And just
strip all trendy tags. Viola it worked!

And ANYWAY. All forum posts, and news items must be available in a SQL database. Can't be that hard to get them into something an Amiga browser can compute. Even if it means "Select from .. where .. and printf()"..

Writing a new browser may work, but there's a risk that machines with little RAM or low Kickstart version will suffer. Many programmers seem to not consider that all that nice program code uses resources.