Scala needs a new "official stack", hopefully Mill + utest/Munit + scalafmt (with opinionated settings).
Scala 3 + SBT + Scalatest + whatever formatting isn't going to grab folk's attention.
Maybe so... but so do Python or Javascript. It seems to me some other languages have only one stack (rust: cargo, rustfmt...; the .net world as well). Does it make them better? (honest question). Then again, what's Java official stack?
The only problem is, once you've tried out Rust, it will be difficult for you to come back to Scala.
I no longer program in Scala, but I used to for my previous job and I regularly came across build files I couldn't understand -- and when I asked the person who wrote them, they couldn't explain their build properly either.
And this happened in enough cases that I wouldn't consider it an exception or a problem with a particular developer. SBT used to have two entirely separate syntaxes, and it was a mess translating from one to the other. I don't know if this is still the case (I know one of the two syntaxes got deprecated, can't remember which one now).
The proponents of the approach that sbt takes have failed to realise that build tools have zero value whatsoever, every second spent on them is a second wasted.
What you want is a good mix simplicity (yes copy paste is fine) and some basic examples to follow, and the ability to break out into script if you are doing something unusual.
Especially for those coming from languages like Python and Go, where the former has no build system (ignoring setup.py), or an almost universal one (go build, sometimes make).
All of the projects I have touched are documented using sbt, and transitioning the build process for existing code projects while a new language learner is a double cognitive load.
If you're dealing with dependencies only, then it's a straightforward change. OTOH I've never had an issue with SBT since it's cleanup a couple of years back so YMMV.
If you're not, the documentation is missing as you say. Maven does just work, but the documentation assumes you're using Java.
You use alternatives at your own peril. This means you won't be able to understand other people's builds, for example.
I know some Scala projects use Maven instead. Whether that's a good idea is debatable!
The tradeoff is with SBT, you won't be able to understand your own builds!
(This is kind of a joke, but not really...)