You have to put the cost into perspective. If your work is worth 20€ an hour, then 600€ (ignoring the cross grade offer) is worth 30 hours. If Dorico speeds up your work by only 2%, that will pay back the 30 hours in a year and Dorico was effectively free. (And from my experience, you save a lot more time than 2%).
Of course if you don’t make any money from what you do (or from anywhere else if you are student etc) that logic might not apply to you!
I wonder if anybody makes money from the notation options in Notion - they used to be pretty primitive, and last time I looked (not recently) Notion didn’t even have a demo version, you just had to believe how wonderful it all was from their website. Paying 80€ with that little information really is taking a shot in the dark IMO!