It still boggles my mind that Half-Life 2's release was 16 years ago at this point. Yup, we've been waiting for Half-Life 3 for at least 15 of those, and amazingly, fan demand has never died down in that time.
Finally, we're getting something of a follow-up, albeit in the form of a VR-only prequel to Half-Life 2. The good news though is this seems to be only the start of Valve's return to the Half-Life series, at least according to Valve's Robin Walker.
Speaking to Game Informer, Robin stated that the Half-Life series means a lot of Valve, and that the company have reconnected to the franchise during the development of Half-Life: Alyx.
There are Half-Life: Alyx team members who have been at Valve since Half-Life 2, and quite a few who go back to the original Half-Life. There are also people on the team for whom Half-Life: Alyx is their first time working on this series at all—and many of them certainly hope it's not the last. We absolutely see Half-Life: Alyx as our return to this world, not the end of it.
This is far from official confirmation of future Half-Life games, but it seems likely based on Walker's comments. In the mean time, Half-Life: Alyx is just around the corner, and will release on the 23rd of March.
Valve's Index VR headset has been in huge demand and has been sold out for a while now. There's new stock coming Monday, but Valve warns it expects them to sell out quickly.