Nah, they won't be back. It's not quite the love in you're thinking of there, it's just people being civil, having discussions and generally it's currently all quite nice. What it is, is people (and in particular well known people) being tired of having everything they post hijacked by "blue tick" payers with agendas, angry shouty people, crypto ads and bot farm noise. As I said previously, it's not about deriding or being against free speech, it's not wanting to deal with arseholes. I think that's something anyone right minded would get behind, regardless of political persuasion.
When Twitter first started, it wasn't a particularly political platform, but became a firestorm in that arena. Many people don't want to engage with that on social media, and that's absolutely understandable, and fair enough. The only place I talk politics online (in reality) is here (and I don't even really do that all that much).
(By the way, Sopel didn't announce he was leaving Twitter. He said he was going to go to Bluesky, but would pop into Twitter occasionally. Which is what he's done).