I used to, quite heavily. It was my go-to systems language when I didn't have any particular reason to use C or C++. But I think its time has likely gone at this point. It honestly just doesn't offer anything that interesting compared to other languages. As others have pointed out, C# is in many ways its spiritual successor. Go offers a much richer library collection, is similarly lightweight, but has a better resource cleanup story (both defer and garbage collection). Rust offers an even lighter weight runtime and throws in rich concurrency and safety guarantees. FreePascal offers...safer strings than C, I guess?

I honestly prefer FreePascal to C, but I just think that ship has sailed at this point.