Oculus Quest 128 GB back in stock @ Oculus site $499

This has been in and out of stock everywhere even months before the pandemic. This video, while a bit old, provides some quick, hard stats on why the Quest is so popular that it's a deal even at MSRP: https://youtu.be/WMlckGWPENc.

In one word -- WIRELESS. You don't need a PC. You don't need cords/wires. You don't need lighthouses. You just put it on and start playing games anywhere inside your home, or outside your home, with complete freedom and no tripping over cords. Everything is self-contained and ready to play games anywhere you go for a very reasonable MSRP starting at $399. As such, it is very accessible to newcomers who don't own VR capable PC's. It also appeals to enthusiasts who do own VR capable PC's and want to play PCVR games un-tethered, while still keeping it affordable (see #3 below). This wide range of appeal makes the Quest one of the most versatile VR headsets currently on the market.

If you have a VR capable PC, then yes. There are 2 main methods to play PCVR games on the Quest:

• Wired -- buy an Oculus Link cable and connect it between the Quest and a VR capable PC. The official Oculus Link cable is $79 MSRP. You could also buy an aftermarket USB 3.0 cable starting in the $20's. And with the latest Update 17, Oculus has added support for USB 2.0 cables, such as the 10 ft charging cable that is included with the Quest so you could play PCVR games right out of the box.
• Wireless -- use Virtual Desktop app (make sure it's the version for the Quest, normally $20), or a number of free apps like ALVR, or try the free Radeon ReLive VR if you have a newish AMD GPU in your PC. You would also need a good 5GHz wifi router. Once setup properly, wireless works about as well as wired and still keeps you un-tethered. This video could help you troubleshoot most wireless issues you may encounter: https://youtu.be/Bm4kbHeXGrg.

Some people are prone to motion sickness, others are not. If you fall into the former group, don't fret. Rest assured that many VR game developers are aware of this and have made accommodations in their VR games to minimize motion sickness. Take Half-Life Alyx for example, there are about 4 ways to move around inside the game, starting with the most comfortable (and least motion-sick inducing) "blink" movement. Many other VR games have similar accommodations. Unfortunately some games cannot get around this, such as car racing games. You can't exactly teleport your car around a track. This applies to any VR headsets, not just the Quest. Personally, I am extremely motion sick prone, and I am fine with 90% of games I play on the Quest. Some people also claim you could slowly condition yourself to be less motion sick prone, similar to how sailors get their sea legs. In addition, Oculus store has a comfort level rating for each game. If you are really sensitive, stick with "Comfortable" rated games. But not to worry, some of the best and most popular VR games are all rated Comfortable such as Beat Saber, SuperHot, Moss...etc.

Yes. It plays very well on the Quest as reported by many. See #3 above.

Depends on the size of your glasses frame. But most people still end up being uncomfortable after prolonged sessions. Look into prescription VR lenses. They make them for just about every VR headsets on the market. Many options are available ranging from cheap DIY to the expensive. For example, I paid $45 total for my pair of magnetic prescription lenses that quickly pop in and out of the Quest. Most people find these much more comfortable than wearing glasses inside the Quest.

Yes. SideQuest is your friend. There are great unofficial games you could sideload, such as Pavlov.

Predicting the future is always tough, especially when very little official information has been released. So I would personally not even try to tell you what to do. But if you must know, I would instead refer you to the community enthusiasts. Most of these guys follow VR news much longer and closer than probably most of us do, thus they may have better outlook. But again, don't take these predictions as gospels as no one knows the future for certain. Here is a very recent prediction video from one such VR community enthusiasts. If you just want the condensed version, he predicts the next version of the Quest would be released in May of 2021: https://youtu.be/YNtAcCHQINs.