Am I shooting myself in the foot by choosing not to do anything with Frontend?

I'm looking for opinions and thoughts from folks who have been in the industry for a while.

I have about 4-5 years of experience so far, so mid-level-ish. All I've worked with so far has been almost exclusively backend. Early on I used C# to develop a couple of Windows desktop tools using MVS WinForms to create a GUI (drag and drop kinda thing) and then wiring the buttons for the logic. This was for some internal work processes that helped reduce manual labor and saved a lot of time.

Later on I moved to a different role that is 100% Java/SpringBoot/Oracle stack. It's in a web-development environment where we connect to external services through REST APIs, Websockets etc., but I have nothing to do at all with the Frontend, there is a dedicated team for that. There are a couple guys (rare) who do sometimes work on both the Frontend and Backend when something needs to be done quickly with a lack of help available.

As part of my degree, I've worked on developing a C++ Windows desktop tool for financial calculations using Qt. The GUI was also built with drag-and-drop system and wiring.

When I first started progamming in my own time, I played around a bit with HTML/CSS/JavaScript, and while I got things done - I didn't particulrary enjoy it. I prefer to be working on the "business logic" behind the scenes, that is a lot more interesting to me than the creative aspect of Frontend and trying to make something look good, organized etc. I'm also in general not a big fan of the Frontend ecosystem with the restriction to just JavaScript/TypeScript and the plethora of other libraries to build the UI.

I ask because I see a lot of positions that require Frontend experience/willingness or simply Fullstack who can do everything. I don't have any experience with Frontend so I don't think I can pass those requirements, which makes me feel incapable and gets me worried. I'm wondering if this is hurting my long-term career prospects of losing out on opportunities that I could've otherwise had, had I chosen to do Frontend too?

I'm definitely not forgoing backend, but it's a question of being a backend or fullstack. Is it better to be a jack of all trades or specialize in something I can truly hone my skills into and become an expert in? What are the long-term side-effects of choosing to avoid Frontend/Fullstack?