In my opinion, buying and holdingbitcoin is not that effective anymore due to the reasons that its value is higher than usual unless bitcoin could double its value today. The reasons many investors became rich in buying and holding bitcoin is because that they bought bitcoin much earlier.
While I see what you are saying, this same comment could have been made 3-4 months ago when bitcoin price was in the low thousands. A lot of people thought that would be close to the peak and it would be difficult to see returns like 50-100%. I'm not saying that bitcoin will or won't double in value again in the next 4 months, but what I'm saying is a lot of traditional trading strategies and trading norms do not hold true for bitcoin at the moment.