Would high volatility also be a problem if the high volatility is heavily skewed to the upside? You can´t
underestimate the importance of the continuous block reward halvings. These events should always put upward
pressure on the BTC price and therefore in the long-term Bitcoin should always go up.
Other developments like the continuous loss of BTC that are lost/inaccessible forever, also
decreases the available supply even further.
That would only be true if Bitcoin had no competitors - not only cryptocurrencies, but also gold and other "real world" assets, and if all Bitcoiners were hodlers (and nobody would sell sometimes to take profits).
And I think people are over-estimating the influence of block halvings. Block halvings only reduce
supply inflation by the half, the impact on
total supply available on exchanges is much more limited (because miners are, by far, not the only people selling BTC). But inflation is already pretty low.
The long-term bull market we're still in (despite the last bearish months) is mainly caused by the fact that Bitcoin is still a new asset, and only in 2017 it achieved a significant "market cap". I believe that there's still potential to the upside, but the phenomenal gains from the last years will not be possible anymore. The curve will be flatter and flatter, and bearish/sideways phases will tend to be longer.
But at a certain price point (e.g. when BTC goes up another 20x from here) people will be forced
to reconsider their fear of a volatile asset out of simple self-interest. You can´t ignore it when
all your peers are getting more wealthy due to BTC forever.
If Bitcoin goes up other 20x then it will be probably a bad moment to buy. The price increases do not "come out of thin air", you must always take into account that if you want to profit from simple hodling, then after a certain time you'll want to sell (for other currencies or goods/services) them for significantly more to
another person who also thinks he/she will make profit, and so on. That cannot go on infinitely, so there will always be crashes, and at some moment the long term bull market will transform into a sideways market, but still with crazy swings. The only way to fix that is to use it more like a currency.