I also talked about this recently in arguing that Bitcoin needs to be easier and more convenient to use for it to truly gain mass adoption. And I'm not just talking about "having" Bitcoin or investing as majority of people who say they do actually just keep it on exchanges or worse, have something on Paypal or similar that isn't even really BTC.
Underlying infrastructure and all that yes, but the interface on top also needs to be very good. And the "fiat ramps" as they say.
Bitcoin is pretty easy to use. I mean at least as easy as it comes in the crypto world. The usage issue is being solved with the Lightning Network pretty well I'd say. There is almost >2k BTC on LN now. So, the usage is definitely growing and it is more a matter of regulatory convenience now rather than technical convenience.
Same for the Fiat ramps. It is mostly about what regulation will allow which will determine how "adoption" grows. There is another way of looking at it though. Even without much regulation, Bitcoin has done well. People who take the time and effort, eventually find ways. Maybe it is better than bitcoin is for self-starters, rather than for those who need to have their hands held all the time to decide whats good for them financially. Most of those people should probably then just stick to Mutual Funds and shit.