Aside from the glaring issues with syntax (the given syntax in general is completely out of place from the rest of the syntax in Scala as others have commented) I would actually like to see some real world non trivial examples (i.e. something equivalent to cats) on the usages of given because
Seems like a very serious limitation, I definitely know that I wouldn’t be able to use given because there is a big difference between something being initialized val/lazy val/def (its also completely out of the place in the Scala language as has been commented elsewhere, everywhere else in Scala when a variable is initialized either implicitly or explicitly you can control how its initialized).
I honestly get the pursuasive feeling that this is being shoved into the language last minute without even properly addressing considerations or seeing if this is going to hold up in the real world. Typically such features would have a proper RFC/hidden behind a flag /plugin in other languages to see if the feature actually justifies itself and that can only be seen when its used in non trivial ways.