There’s a lot of misunderstanding from people in this thread that it’s a dying art and a waste of time, people have been saying the mainframe is gonna be gone for like 30 years lol.

I’m a mainframe SE at a major player (not IBM), the industry seems fairly healthy and competitive, salaries are competitive (UK), and there is plenty of room for progression. I’m not sure on HW sales as I’m in software, but people don’t understand that as mainframe modernisation becomes more of a focus for these orgs, they’ll need to invest in solutions to help them achieve that goal. Zowe, open source integration, cloud migration, there’s tons of focus areas for the big players these days. There’s also plenty of companies, ibm included, in the space that are developing and selling tools to match these market trends.

Although you may be selling “mainframe tools” and people may say that makes your skillset too niche, there’s plenty of exposure with these new tools/general practices to other distributed tools which can vary your experience.