Can I offer thoughts on your considerations?
Some considerations:
1) 2017/2018: about 30 forks have been implemented. They may have influenced BTC price (especially cash and gold).
I don't think this matters. You're not referring to 30 forks on Bitcoin...right? Most of them go unknown so most of them don't influence the price of Bitcoin
2) 2017/2018: BTC Futures. I think they have weakly changed cryptocurrency market.
Futures trade completely separate from the Blockchain, so there's no direct influence on the price from futures trading. Companies taking futures positions or making a market in futures need to buy and hold Bitcoin to serve as reserve for their futures positions (particularly if they're going short), so the futures business is supporting the price of Bitcoin due to that activity.
3) BTC dominance has collapsed in the last 3 years: from 80% to 40%.
Agreed to the decline in dominance, not to a collapse. How are you measuring "80% to 40%"? Of what?
4) Media attention may have influenced last semester.
Sure...but as media has died down so will the "newbie buyer" hype. This will slow the speculation.
5) Scalability problems have transformed Bitcoins in assets.
Lightning Network is coming. And, actually, I think it's the lack of merchants wanting to hold or deal in Bitcoin that's made a greater impact on Bitcoin's utility shifting to an investment class.
Thoughts?
Nice chart, you should explain to us what the logarithmic scale does for charts like this.