I’ve seen roles like that as well, but much less than I used to. I see them more on entry level roles. I’ve never worked frontend and I’ve barely been full stack for several years now. Most of my experience is in .NET stuff, and usually C# is not the “ “x, y, or z”. Usually it’s something along the lines of “Java, Go, Python”. Not that I haven’t ever worked in those languages, but certainly not recently.