with you having answers since 2019 I think you have your questions enough response and time to lock the thread at least .
and also you should explain well what transactions are you referring because you are comparing this to normal currencies in which I think not enough to conclude , this is a virtual currency while you are asking about fiat .
BTC is the crypto king, many people know this but it is strange that many investors still do not want to limit their profits to the weak increase of BTC price compared to many ALTS in the bullrun. Perhaps greed has led them to make riskier choices, and then regret in the present when many ALTS have a weak recovery compared to BTC. BTC has made a new ATH while many ALTS are still in the bottom price zone even though they have very interesting narratives.
I always believe that BTC deserves to be in the investment portfolio, accounting for about 50% to ensure that investors will profit in each bullrun. The remaining 50% can be allocated to ALTS, especially top ALTS like ETH, SOL, XRP... Anyway, I also understand that investors will still want to seek opportunities in ALTS, so to have a better mentality, diversification investment will be more suitable than concentrating 100% of capital on BTC.