Yes, these are good points. They are still being included in projects today.

I recently had a dev contact me and when I reviewed their offer document the promised/guaranteed returns were 250%.
They do not even have a working MVP. This is insane.
While it seems they believe in the project I could not agree to promote on faith.
Get more proof or raise private funds somehow.

Also when they want to "pay with a commission on my actual raised funds".
I say bye-bye to these "opportunities".