So I have been planning to build a SaaS and Ruby on Rails sounds very promising framework as it has been used by many big name companies. Even though I know Django but I planning to get out of my comfort zone and try something new.
If you already like Django and have learned its ins and outs, time spent learning Rails would be better spent actually building something with Django. Also, a lot of big, successful companies have been built with Django, among them Pinterest and Instagram.
With that said, if you want to try something new and need something better suited for scalable, real-time applications, the combination of Elixir & Phoenix is similar to Rails but also less magical, and it runs on a battled-tested runtime with fault-tolerance and low latency built in.
Finally, if you’re building a CRUD-ish SAAS app that needs a constant server connection, check out Phoenix LiveView for a very robust and dev-friendly solution. For the type of apps it was meant for, it’s really the technology to beat (I use it for my day job)!
In the end what matters is that you can produce the functions that make your product valuable to your customers. You need to Do it on a daily basis and always on time. Ruby on Rails helps you with that.
General advice: Do not choose the tech stack for generating your income by following fashion. It is a marathon and not a sprint after all.
I'm currently working in a Typescript environment that somebody choose for "reasons" (types, hiring,...) and I regret it every day. I'd go with Rails anytime.
idk / imho. ... to you want to work on an 1.) "experimental" or "learning project" or 2.) a "serious" one, where you need an MVP fast!?
if 1.) use whatever floats your boat.
if 2.) use whatever tool for the job in question you already know best - for me in your case it sounds like: python django ;)
just my 0.02€