You are not alone. I have a 1080 Ti, and DAINAPP is slow to the point of being unusable. A single movie would take weeks. A 1080 Ti can't even handle 1080p video without running out of memory. Don't buy a new graphics card for this program. It is clear that HUGE improvements are needed for it to be a useful program for consumers (the people who don't have spare 2080 Tis that they can leave running for weeks).
For this program to actually be useful, the devs are going to need to improve speed by 10x and cut memory usage in half, which I don't think is going to happen for many months, if ever. Still a cool proof of concept though.