Personally, I was familiar and a little bit stuck in my ways with PHP and decided to use NodeJS for new projects. It really wasn't much of a learning curve (as @Teodor says, Wappler looks and acts the same irrespective of server model) but have found it to be more responsive and the realtime data future is a huge bonus. The server-side data / security restrict redirect element is also really useful. There is NO WAY I would start a new project now in PHP!
I still have some old PHP projects which I would love to switch to NodeJS but they have hundreds of server actions, have many pages and use Argon pw hashing. @jonl provided an extension for Argon so that can be achieved but the prospect of copy/pasting the JSON for each server action and then adjusting file paths fills me with dread and I just don't have the time to do it. I would love it if @george added the converter to the upcoming features: