Everything
@Maverick5207 just said! Braid to a Fluoro leader is so versatile you may never set your gear up any other way.
There are couple other benefits and reminders about this combo as well.
Braided last forever and as mentioned above it has no memory, so you will be replacing it much less often. I have some braided line on one of my reels that I’ve had on there for 10+ years (although I could probably benefit from replacing, it still seems to be going strong).
The other benefit of using 20lb braid to a 6, 8, 10, 12…whatever lb. fluoro is that you are much more versatile with your lure weights and sizes (assuming you are on a versatile rod paired with that reel).
Also, if you want to go after more toothy fish and not use a steel leader, just cutoff your fluoro leader and go straight to braid. It will hold up better once hooked up.
One thing I would say to remember when tying your fluoro leader to your braid (I use a double uni knot or a blood knot) is that braided line is pretty slippery, its diameter for the same lb test is much smaller (so you have a lot more running line for bigger fish). Given its smaller diameter, you may notice that your 8lb fluoro is larger in diameter than the braid (not an issue for reel capacity) but can become an issue with knot construction. So just be sure (if using a double uni that you have more twists on the braid side then you do on the fluoro side. I usually use 3-4 on the fluoro cinch knot side and up to 6-8 on the fluoro side. This way the opposing knots are more equal in size.
I do this as I’ve actually had the braid knot, which is smaller with the same amount of twists, pull through the fluoro side.
My hard core slip bobber Walleye friends out of Minnesota think I’m crazy with my braid/fluoro leader setup. They are straight mono or fluoro guys. And I think for that particular application (slip bobber fishing) fluoro or mono is superior. Primarily because the bobber slides better IMO on mono/fluoro than braid making it is easier to set proper depths and using less split shot above your hook and bait, also, the bobber can’t slide past the double uni knot. So you are limited with depth, unless you use a very long fluoro leader 20ft or so and put the bobber and stop below the braid.
Other than that, IMO it’s a superior setup.
Hopefully that makes sense.