These bezels are done with 3d geometry, not flat 2d textures, which has some advantages and disadvantages.
The advantage is they look beautiful if you zoom way in and marvel at the nav/comms panels.
The disadvantage is that when they’re viewed at a distance where the bezel lines are about one pixel tall, there are major aliasing problems that can’t be solved with automatic mip-mapping/filtering like a flat texture. It has to draw actual polygons, and the antialiasing isn’t quite good enough to keep the line looking clean from frame to frame.
I think the only thing that can be done really is to use supersampling – set the render scaling setting over 100% so it renders at a higher resolution than your display, then scales it down more smoothly and consistently than the TAA antialiasing can do.
However this will MASSIVELY slow down your sim. At 4k if I switch scaling up to 200% (the max) my frame rate drops below 1 fps and it took me about 5 minutes of waiting for the screen to update to set it back down to 100% or 80% where I normally keep it. Be very careful with this setting!
More generally, double-check that your antialiasing setting is TAA, not any of the other values which all look much worse than TAA. But even at TAA at 4k resolution I see roughly the same effect when panning the cockpit view in the C152.
You may just have to live with it, alas. 