My background is Audio/Video, Automation, and general low voltage systems.
However, I've been out of the game for awhile.
This is a very hard question. It really depends on so many things. Budget, desires, priorities, reliability.
I'm renovating a house right now for myself. A man clubhouse as it were. I'm starting with my No Gurls Aloud
sign.
I'm hard wiring the surround sound for a number of reasons: Price, quality, and I can do it myself. I love the sound quality and value of Polk speakers as well as Klipsch. I'd put either up against Bose, or any other overpriced system, with the right setup, at half the price or less.
Wireless gives you freedom from hardwired but can create wireless headaches. Hardwired just works. Wireless needs bandwidth and can be interfered with. Hardwired makes changes difficult and installation can be expensive.
As far as sources, it depends. If you want the free stuff, a firestick with Koni and a VPN? So many choices. If you want pay stuff, there are so many choices based on what you want to see or be able to do.
This world is wide and deep. The first things you decide are budget and priorities, like movies for a theater buff vs music for an audiophile. Set a budget. Decide that first, so you have a frame of reference.
As a rule of thumb, for now at least as I understand it, hardwired quality and value is better and more economical, if you're handy, but it does take some skills and work. Wireless is more easily installed, expandable, and could be a better value if you change things around a lot.
You can also do both like in a theater where you hardwire the front 3 speakers and sub, the easiest to do, and go wireless on the surround.
Soundbars are great. I remember their birth. But they are no match to a real surround system if you enjoy full immersion. Great, in their own way, but no comparison to surround. But great, in their own way, may be exactly what you're looking for.