I think the built in themes look good and cover a lot of styles including MUI very well, but I personally like Ant Design aesthetic a lot and it isn't really matched by any existing PrimeReact themes.
I made a list of side-by-side comparisons where Antd differs:
Interactables - Antd has a subtle ripple animation outside buttons on click. PrimeReact themes only have MUI-style ripples inside the button or no animation.
Highlightable components - Antd has a thinner border. PrimeReact themes all have a thick borders like Bootstrap
Tabs - PrimeReact shows a highlight border after clicking tabs which looks weird
Menus - Antd highlights menu items when clicked. PrimeReact menu doesn't do this. Listbox does, but looks different.
If there was a theme that tweaked those differences I would be left with zero reasons to ever pick Ant Design (or any other library) over PrimeReact 😉
You can tweak all this with PrimeReact Theme Designer or if your using a premium theme it's all configurable with SASS. You could easily tweak to make it how you want it above!
I think the built in themes look good and cover a lot of styles including MUI very well, but I personally like Ant Design aesthetic a lot and it isn't really matched by any existing PrimeReact themes.
I made a list of side-by-side comparisons where Antd differs:
If there was a theme that tweaked those differences I would be left with zero reasons to ever pick Ant Design (or any other library) over PrimeReact 😉