The seasoning it makes it non stick - not the iron itself. In theory a heavy enough stainless steel pan would have roughly the same heat capacity but stuff would still stick.
There's a few modern non stick coatings - ceramic based ones that might work with a sufficiently heavy base. Essentially though, you want something I've not seen on the market yet.
On the other hand, babying your cast iron is both a modern thing and "modern" seasoning methods are meant to make it easy/consistant once you know what you're doing. As long as you use it oftenish, and don't completely strip out the existing seasoning without redoing it you should be fine.
In India, there was also a habit of simply coating cast iron in fairly heavy edible oil (I remember mom mentioning castor oil) and wrapping it in leaves (but we live in the modern age! Greaseproof or parchment paper would likely serve the same purpose), so much like with anything nice, it needs a bit of care and maintenance.
Also, cast stainless steel isn't a thing. Cast iron is a specific product and a specific alloy. You're likely better off forging steel, just to the same dimensions, and there's likely no magic in the fact that its cast. It just has very good characteristics and a good amount of heft