If you were to say "hey, we should all fight for foobardom, a new term I just made up" but didn't give a good definition for then, yes, you'd have a problem: talking about foobardom would be pointless since it's an ill-defined term and the discussion would serve no purpose.
However, this discussion about philosophy and freedom is the reverse: people are already fighting and in many cases dying for what they think is this thing called 'freedom', and yet it proves elusive to find a definition.
The real-world, societal impact is already there. So it's worth studying.
And if you study it and find that it's elusive and nearly impossible to pin down... well now that's interesting, and should make you think critically about anyone who uses the term as a low-nuance bludgeon in an argument.
(In the other article around Twitter here today - this thread - https://twitter.com/yishan/status/1586955288061452289 , I think this point is made pretty clear early on by the spam example: perfectly legal, yet "bots" are a self-professed problem for pro-whatever-speech-is-legal,don't-get-involved-further Musk...)