Ah yes the Star Wars equivalent of "If everyone is special, then no-one is".
That was a plot point I hated. Or rather I hated the interpretation of it as "Anyone can be a Jedi/Sith/Whatever".
No, not everyone can. Everyone might have a "Connection" but that doesn't mean everyone should be able to mind trick, force pull etc
For 99.999999999999999999999% of beings in the Star Wars Universe, their connection to the force should be so subtle as to be practically un-noticeable. Like deja vu, or being able to tell when someone is standing behind you.
Force users are supposed to be so rare most people will never even see one. Or even know anyone who has. They should be legends, especially the further away from the core systems they go.
As for having to have a special lineage or come from a family of force users that has
never been the case. It's a Midichlorian lottery.
You need to have a special lineage if you want to be "The chosen one".
Is the Skywalker-line special? Yes. But being spontaneously conceived by the universe will do that. Plus the first six movies were explicitly about this family so I can understand it focussing on them.
I think they got it wrong by making Rey ole Palps Grand Daughter though. I swear they should have just been upfront with who Rey was at the start and made her Han and Leia's daughter or something. Brother V Sister would have been a much better dynamic than the weird relationship they had and it would have fit with the movies being about the Skywalker family.
But outside of the movies, there's never been any indication that only certain families are strong. The books, games, comics and other shows are full of characters that can use the Force that aren't from any well known families.
The second the force becomes something potentially EVERY character can fully access it stops being special.
Spoilers for Ahsoka... kinda
Which makes Sabine a tricky one. By all means give her some trauma or something that has suppressed her abilities and Ahsoka can sense it and has to help her unlock that. I can get behind that. But this idea that all you need to do is practice hard enough and really want it just seems bollocks to me.
Or they could have done something really interesting and adapted one of the plotlines from the Legends timeline, where Callista (Luke's girlfriend at the time), who was a fully trained Jedi gets cut off from the force. Eventually she finds out that she can get her power back, but only by drawing on the dark side. Give that story to Sabine and it would have been strawberry floating great. She finds out that she can stop Thrawn but she would have to call on all her anger and hate to do it.
Right now I'm willing to look the other way about it all and just assume that she must have had some repressed latent Force ability that she wasn't aware of and couldn't tap into. That's the only way it works for me. But then I really dislike Last Jedi and most of what it did, so it's not surprising I'm not a fan of this interpretation of it.