Not Recently. 2010ish was working for an insurance processor that was actively writing thousands of lines and executing on z/OS with no plans to migrate.

I was part of team that was writing web applications that needed to call z/OS transactions. The IBM solution was to use their Transaction Gateway product, which cost a ton, and was slow as shit. We developed a framework that used annotations on the Java Side to map COBOL Records to Java Objects and invoke transactions over a TCP socket. Learning how to pack decimals and convert encodings was pretty cool. We ended up with a framework that was at least a zillion times faster than the IBM solution. Left that job though as the company was is distress and was losing customers (health plans). They eventually folded.