You should be able to differentiate between a $1,000,000 marketcap and $1 trillion market cap. Most Bitcoiners are unable to do so. They believe in it rising to infinity and beyond because of previous movements.
I don't think it's just based on past performance but on the notion of
exponentially increasing adoption. It's still known that significantly more money will be needed to sustain the price as it increases.
The last time Bitcoin shot up in price, any transaction cost $50 to do. A big speaking point for Bitcoin used to be that you could do small transactions for virtually no cost. This all changed once it shot up.
The ethos suddenly changed to being that Bitcoin should only be for large payments only. $1-2 payments shouldn't have any consideration.
That's really an exaggeration of fees last year. $1-2 fees for quickly confirmed transactions yeah, but anyone paying more than that was doing so unnecessarily (or was using lots of inputs). Transaction batching and Segwit adoption have definitely improved things since then and Lightning transactions are extremely cheap and fast.
I never bought into the "cheap fees" selling point because that's not really part of Bitcoin's design. But micropayments can be a reality as the Lightning Network becomes more usable.