In concur. A buddy of mine is doing a lot of stock trading and has also dabbled in forex and crypto a bit, and according to him it's very different. The basic rules still apply, but much less reliably. Nonetheless I guess it's mostly a matter of experience, so if you know your technicals and watch the crypto markets a bit you should be able to take your own lessons on which techniques work and which don't.
I also come from a traditional trading background. I think the reason for what your buddy observes is that the big hedge funds use algorithmic trading systems and these are not present on crypto. A lot of those algorithms are built from technical patterns and because the big players are using them they become a self-fulfilling prophecy. There are some trading bots available for crypto but their systems are highly primitive in comparison.
That makes sense. I didn't account for automated high frequency trading, but I also assumed that part of what makes technical analysis less applicable to crypto is the general lack of trading expertise creating a more random market. Add to that relatively low trading volume and you get every pumper's dream and every technical analyst's nightmare.