That's sort of what Java-supporting feature phones are meant to do, but I don't think there are many apps available and supported (WhatsApp probably still is). I got by with Opera Mini on a feature phone for years, it was painful to use but still handy.

The issue is that people have differing opinions as to what those essential apps should be... I'd imagine that it's hard to get consensus around what you need.

For what it's worth I've been trying to have a more "dumb phone" experience recently, but not by having an extremely small amount of apps. I simply removed all of the ones that are sources of distractions on a daily basis. The biggest culprit for me is Chrome. I'm realizing that I really don't have any need to have access to the entirety of the internet at all times. A couple dozen apps will give me what I actually need, and no distractions or aimlessly browsing [HN, Reddit, Facebook Instagram, etc.]