What it suggests is that in that particular game, your GPU is the limiting factor.
If it's good or not, really depends on the game experience you're getting. If it's running smoothly and you're not noticing any problems then, it's fine. If you are finding it is slowing down in places and ruining the experience then there is a problem.
If you are having problems then you could try lowering the detail and/or resolution settings for the game and see it that reduces the GPU load, and improves the gameplay.
If you're not having problems then I wouldn't bother and I wouldn't worry about it. You've paid for the GPU you want to put it some use. What would be the point of shelling out for a 2080ti and running it at 20% !? [ 100% sounds like value for money to me ]
Remember all games are different. That number of 50% CPU could be a case of the game not utilising all the cores [depending on how that number is calculated] and so it could be that both CPU and GPU are maxed out and in perfect harmony.
The bottom line is to look at the screen and the game as you are playing, not the benchmark %, Temp, FPS. Unless you're noticing a problem then you should investigate.
Install G-force Experience and see if that has optimised settings for your game and that you have the latest drivers.
If you are still having problems and you can't live with lower settings, then it's likely that a GPU upgrade is the only thing that will help. Although to a point your CPU will then become the limiting factor.
The CPU is 2 core/4 threads. So if two of the threads are maxed out at or close to 100% load then the CPU is effectively effectively maxed out at 50% since that's all those threads are capable of. Most games, even multi-threaded games, are depending on one core for most of the performance.
You have to look at all threads to find the most heavily loaded thread. Right click on windows task bar open Task Manager, performance tab, right click on CPU chart, Change Graph to: Logical Processors. Most likely you'll see one or two threads extremely heavily loaded in gaming action. It's going to be the thread that peaks at 100% that is bottlenecking the gaming action even if all other threads are much lower.