...I got a question & it is a serious question .....
if you are going to connect 15-30ft of Flouro leader to the braid, then why do it at all ?
The fluoro is nearly invisible and the braid isn't. So you want this fish to see (or not see in this case) the fluoro.
Fluoro is not fun to run a full spool of on a spinning real. Line twist is an issue even with a swivel. Braid has no memory and isn't impacted by twisting in the same way fluoro is. So braid is superior to run on a spinning reel.
So a union of two line types give you the best of both worlds.