You know, the simple fact a coin is called Bitcoin doesn't make it worth a lot. See all the Bitcoin forks.
Also a newly made coin may or may not become valuable, see the altcoins, in huge numbers being disappointing for the investors.
And, as a bottom line, the fact a coin (like bitcoin) worth a lot doesn't mean the world/the people get rich. No. Only few of the investors.

This being said, creating a new bitcoin may not make sense, especially if it'll be just a clone. I'd expect people will work in Satoshis in 50-100 years to overcome the price rise, but not much else.
So creating a new coin can (only) make sense if it brings something really new and useful to the ecosystem. And that's not related to the price of the competitor coins. Also that can be done now too, no need to wait 50 years. Again, see the altcoins, some did bring new useful features and some of those are going pretty much OK.

The funny thing is that very thing has been ocuring during all the life of Bitcoin, its called "altcoins"... Doesn't mean they will succeed.

What will be certain is that bitcoin will still exist or be used in the next 100 years. Thinking about that is too far-fetched and makes no sense at the moment. We're in the present, so let's try to have more bitcoins than others, that's what we should be more concerned with than thinking about the next 100 years.

What would be benefits of a fork form the beginning? They cannot obtain Bitcoin or fork coin because of the fork. I'm not sure if the OP is familiar with Bitcoin fork. Forking new coins would be similar to Ravencoin (RVN), which claims to be a Bitcoin fork with a different supply. It has no monetary value, unlike Bitcoin. Or another type of fork, such as Bitcoin Cash, which is a waste of time for the community. None of them are competitive with Bitcoin or anything similar. Rather, I believe that when the next generation learns about Bitcoin, they will develop a different currency than Bitcoin. It will not harm Bitcoin's existence.

It won't be bitcoin anyway. People already attempted doing this and then we have Bitcoin Cash, Bitcoin Gold, Bitcoin SV, Bitcoin Diamond, Super Bitcoin... And much more.

Well, better to have 0.0001BTC with Bitcoin pricing 100,000$-200,000$ than owning 1 Bitcoin Something pricing 0,01$.

Younger generations should start with bitcoin like the previous ones. The search for an improved bitcoin has already lead many investors into losing money to pump and dump schemes through altcoins. And if they continue thinking like this, younger generations are going to lose more money yet.

There have been a lot of Bitcoin fork after Bitcoin cash, and none has made half the impact Bitcoin has done. 50-100 years is too far to guess what to expect the present forks is enough to give a picture of what to expect if the future generation tries to fork Bitcoin because they feel they missed the early accumulation phase it will only end up in altcoin projects except there will be a different ledger system more advanced than the blockchain anything that operate on the blockchain as a crypto currency forked from Bitcoin remains altcoin.

Yep this is true if the young generation started all over again the chain this will called altcoin even though is the technology that used is same thing as the bitcoin did.

In my perspective the way we called "Bitcoin" is only one the fork of bitcoin is altcoin and that's it

Just take a look at al the forks and altcoins which have existed over the years and you will see that such a thing does not matter at all, at the same time your argument is really weak because if that was enough of a reason to reboot bitcoin then why not do the same with the whole economy? After all now most of the wealth is concentrated in a few hands and some may think of this as unfair and yet we do not do it, so while I can see why some may think it is unfair other users have so many coins when they have almost nothing, this is not enough of a reason to do this.

I guess it could happen. But if they want to get 1 full bitcoin, they can look for it and try to trade with stable coin pair altcoins because that's what we've been doing. As long as they can do these methods and they can find out how they can get 1 bitcoin, they can have a lot of bitcoins, especially if they can analyze bitcoins.

When the price of bitcoin is like it's out of reach for most people but they can still try to get it in various ways, they will do it. Even though that means they have to fork bitcoin again because their goal is still to have 1 full bitcoin.

Accumulating bitcoin isn't that easy because the value nowadays is really high but if you know how to trade altcoin then for sure in the time that you gather enough profit then you can purchase one and keep it for holding , but of course this will take time.,effort and courage same as Knowledge to gain that much.
it took me years before finally hot my whole bitcoin..