If that's "forced speech", (which is doubtful imo)
Forgive us if we're not convinced more by your vague assertions than the judgement produced by the Supreme Court. But at least you didn't say "imho", I guess...
I think you should listen to the posters above, who do in fact know what they're talking about. To sum up, again: the Equality Act forbids discrimination on the basis of a protected characteristic (or the perception, true or not, of such), including religion or belief (which also includes lack of religion or belief). That means that you cannot treat someone with a protected characteristic less favourably than someone without it, in otherwise identical circumstances.
(There is a slight caveat, I think, to the example @IWillNoLie uses about Muslim groups, which is that the Equality Act only applies to businesses. I have a hunch that if you are, for example, a charity, you can limit your services to people whose aims roughly correspond with yours. I am part of a Quaker Meeting which rents the space to other groups and I think we actually have a responsibility to make sure we do this.)
Compelled speech - which does, yes, in fact include writing words, saying words, singing words, etc etc. - is a different issue. Not discriminating against people who disagree with you does not require you to pretend that you agree with them.