Nice thread you got going here, @philipma1957!
Looking back at 2017, I have no idea why it was so bullish, especially after April or so: 20X in 8-9 mo.
One possibility is that bitcoin did not succumb to "corporate" interests and did not (in the main branch) implement the much bigger blocks. There was a fork, but a clear majority went against people like Circle/Coinbase/Bitmain. This reinforced bitcoin "independence" and probably caused an increase in perceived value.
Looking at now: exactly the opposite had happened. Bitcoin is now a part of the tradfi system through which we should expect larger money flows, in eventuality.
This suggests, that instead of acceleration, bitcoin price curve would decelerate, in my opinion, to maybe 30% or at the absolute maximum, 40% a year (on average).
30% in 5 years from the $49K local maximum would mean about $181K by Jan 2029 (market cap of roughly 3.8 tril).
40% would mean about $263K (total market cap roughly 5.5 tril or 46% of gold).
I don't see 500K in 2025, but I did not see 20K in 2017 either
EDIT: btw, gold did about 5X in 7 years after the ETF approval. As bitcoin is "faster", it can do the same 5X in less than 7, so a 5 years "number" seems reasonable to me. 7 years (in Jan 2031) is the longest time for bitcoin to 5X to about 240-250K that I can envision.