I believe there's a small faction in the community that has accepted that "Satoshi" has ALREADY come out with "Bitcoin 2.0". They call it,

Bitcoin Cash SV, Satoshi's Vision.

But deep inside they know it's stupid.

Whatever might be the technology with the bitcoin 2.0, one that existed initially will hold the value. The second version will be the one derived from the first one. Some user have mentioned it comparing to the ethereum classic, still ethereum leads the market. Ethereum classic gained good support just because of ethereum. Same will happen with bitcoin 2.0 as well.

I won't, you know why? Satoshi is no longer the owner of bitcoin (he intentionally created the technology to evolve that way). We know he's the founder but gone are the days one individual have control over how a decentralized system is operated. Bitcoin have grown more than Satoshi and he/she/them knows that too. Him bringing out another bitcoin, bitcoin2.0 will just be considered as another wanna be bitcoin (shitcoin) by me even though he proves his identity through signing a signature message from his know address. This days nothing is impossible, hackers are capable of doing anything.

Short answer: Yes, I will use it.

Satoshi or others, it does not depend on people, but the technology developed.
Most altcoins are shit-copies of BTC so it will not be better than it.

If Satoshi returns with better technology, it will add to BTC "as it will receive quick acceptance" but that does not mean the need to cancel or stop dealing with bitcoin, something like Ubuntu or mint.

Firstly, what you mentioned would never happen since Satoshi is not dumb to sabotage Bitcoin by introducing a new version in this aspect. Didn't you observe the current state of the Bitcoin related forks op?

Bitcoin cash is the only successful fork which itself is mired in a bucket load of controversies.

yes, I would, just like we risks trying out for new altcoins we are surely gonna try bitcoin 2.0 too. maybe it will come with plenty of new features but that doesn't mean we are gonna leave the old bitcoin system.bitcoin was really unexpected from the start, no matter how well someone understands the inner workings of this coin they still need a lot of external skills to grab some handfull of digital coins.

I will carefully examine the feature of this so-called Bitcoin 2.0. To be fair, I am using Bitcoin not just because of Satoshi, but about its functionality and usefulness for this world.
Conversely, I will use Bitcoin 2.0 invented by a random guy if I see it is superior to BTC. However, I doubt it

I believe even if he or she proves his identity as Satoshi, most people still would not prefer the new coin over Bitcoin. I think it is about adoption but it may reach #2 in the market if satoshi is really serious about that  

let`s say he created away to completely stop 51% attacks he added voting where each address that is verified could anyone get 1 vote something to stop spam and viewbots and fake voting numbers
he made a way to make the chain much smaller (it will be like bigger then my 500gb hard drive soon)
he made a "side chain" that redistributes tax to unique wallets which creates universal basic income
instead of waiting 10 minutes for a transaction you only have to wait 1 millisecond
etc etc he just made it better.  
or stuff along those lines.

 
I mean you all run the bought windows right? how many are still on windows 95? or me? or running ms dos?
I mean you could still run them if you want but they are not supported only the new edition of windows gets new anti virus protection and has updates pushed to it

I highly doubt Satoshi would do any such stupid things, provided we are considering real satoshi here! Otherwise it will just end up being similar to BSV, which obviously we don't want! So I would probably stay with the original bitcoin but will keep the door open for rethinking looking at the community. I alone would not take the decision! So it depends!