I thought we're pretty clear that it's thanks to absolutely colossal mass, which... Can't really happen on earth since it requires the mass of a huge number of earths.
Throwing lumps of cash at fusion power venture capital feels almost like a money-laundering fraud.
Yes. Here are the currently known alternatives off the top of my head:
* Fusion bomb
* Inertial electrostatic confinement (14 year olds have done this for highschool science fair projects)
* Virtual cathodes (Polywell, technically also an IEC variant)
* Magnetic confinement (Tokamaks: the big expensive doughnuts)
* Field-reversed configuration (technically also magnetic, but these are magnetic "smoke rings", Helion Energy does this)
* Z-pinch (again magnetic, but different)
* Laser confinement (NIF)
* Muon-catalyzed fusion (no chance of this becoming mainstream unless we can convince muons to stop decaying)
IIRC all of these have demonstrated that it's physically possible; some even show promise.
(I've been wanting to write a plasma physics simulation to see if I can improve on the Fusor design since I was at university; now chatGPT writes acceptable code, I keep asking myself why I've not yet made this happen…)