Therefore, I would not recommend using it even as a means of payment, for example, paying them for food or some goods, such as a computer or a VPN-subscription, otherwise FOMO will overtake you. When another 10 years have passed and you will calculate how much your payment for the same computer or VPN-subscription now cost. It will be like that story about pizza. Bitcoin is about accumulation, the more you accumulate, the more profit you get.
I have to disagree with you here. Bitcoin is about being a currency. Yes, everyone wants the price gains and everyone wants to accumulate more, but bitcoin is first and foremost a currency. If no one ever used it as a currency, then we wouldn't be where we are today. Sure, if I had never spent a single satoshi then my bitcoin stack would be bigger than it is now, but I'm happy that every satoshi I've spent has helped to grow the bitcoin ecosystem and lead to further adoption, and I'm happy that I've had several years of financial autonomy, holding my own money securely, and not requiring any approval from any third party to spend my own money where I want and when I want. Even Laszlo Hanyecz has said he has no regrets spending 10,000 bitcoin on two pizzas.
And storing all your funds in bitcoin is not feasible as it is not universally accepted and transactions are not instant.
The only transaction which is instant is physical cash traded face to face. Every other fiat method is slower than bitcoin.
But as they say we should not put all our eggs in one basket. While bitcoin is the best coin we should also explore other projects and hold some potential altcoins.
Diversification is a good strategy and we cannot really be sure if bitcoin can keep growing like this forever.
Diversification means putting money in to different sectors, such as stocks, bonds, commodities, property, etc., that aren't intrinsically linked to one another. It does not mean buying a bunch of shitcoins which if bitcoin dumps, they all dump even harder. That does absolutely nothing to reduce the risk of your portfolio.