I live in FL where there are issues with greening and such. I was under the impression that if your trees had been inspected and found to be "clean" (yes, I know that's not necessarily true for the long term) that you could propagate cuttings or let others do so with your trimmings.

Am I mistaken? (I would like to experiment with starting plants for my own use.)

I believe in FL, you can not graft your own citrus.

The relevant regulations can be found in Chap. 5B-62 of the Florida Administrative Code. Technically, if you look at the definition and description of the certified nursery stock certification program, found at 5B-62.001(17) and 5B-62.007, non-commercial, own-use, dooryard citrus propagation is possible, as long as you follow all of the protocols. This involves registration, a specialized facility, acquisition of certified scion material, testing, extensive sanitation procedures, etc... And while the statutes and regulations don't specifically state that the folks at the Division of Plant Industry should laugh at any own-use dooryard grower who requests certification, I don't know that would stop them from doing so (and this isn't to suggest they are callous and unsympathetic; just to say that the regulations are such that they probably prohibit in practice what they seem to allow in theory).
That said, I haven't read the regs exhaustively, so perhaps someone else knows of provisions that I do not.

I didn't read the code; I did find out what it takes to have a "clean greenhouse" for propagation. Holy cow! It's like scrubbing up for surgery to enter the "castle". A few cuttings would never be worth that expense. (And I do understand the issues; I don't raise goats but there are some really horrible diseases that can destroy a clean herd which can be brought to the farm on a pair of shoes/boots.)

Purchasing a "clean plant" does not guarantee that it will remain that way so all this precaution is, IMO, a bit silly. I'll follow the rules but don't think they're valid because they ultimately don't solve the problems.

Okay, this is very strange to me. I was in Walmart and very close to purchasing their last 1 gallon Meyer Lemon--had they discounted it as they should have because it was dry as a bone and losing leaves I would have. They didn't so I didn't but I noticed that the only official "marking" was on the POT. Seriously. I assumed there would be a hang tag on the plant like one of those "do not remove" mattress ones; there wasn't. And who would grow a citrus in citrus country in a 1 gallon pot forever? (Save the pot? No instructions to do so and labels fade so what's the point?) There were instructions to respray/retreat the darling if it hadn't sold by a certain date. But otherwise nothing.

I honestly don't get how FL believes it can enforce plant security in this manner.