Ask HN: Are startups still using Ruby on Rails to start new products/projects?

I'm interested in building some open source projects/libraries, with long term monetization being the addition of paid/premium additional features.

I have a soft spot for (and expertise in) Ruby and Ruby on Rails, but I know it has seen a decline in popularity ove the years.

Are start-ups still using Ruby/Rails to get new apps stood up?

If not, which web frameworks are seeing growth, or big mind share for new builds of SaaS?

Edit: my primary interest is in building libraries for backend processes, than heavy frontend offerings.