I think for your older gamers HL as a franchise may still hold some cache but for many younger people, it's going to be a non-entity. Valve really has done absolutely nothing to keep the franchise front and centre in peoples minds in terms of refreshes etc and it's fallen to the dedicated modding community to still keep it a thing. As someone who was very much Team Valve all the way back when HL released and HL2 emerged I've long since come to view them as a failing company whose continued existence is really the just the result of one extremely financially successful product (Steam) which keeps them afloat. They kind of remind me of Google in that regard. Too much money, but no clear direction (likely not helped by their unconventional management model).
Said it before, but it bears repeating, there was nothing in the Geoff Keightly interview that suggested that Half-Life: Alyx was born out of anything other than the convenient portability of the existing HL assets to the latest source build and it being the most viable of their existing IPs to adapt to VR. As someone who bought into Gabes whole 'Episodic' Shorter games/faster turnaround, a proper conclusion to the HL2 story BS back in the day., I'm just not finding anything here that says 'Day 1' to me even though I own a VR Headset. I don't care Alyx and I don't care about a prequel. I just want Episode 3. That's the storyline that interests me.