“Final Cut Pro is a registered trademark…”
Yes, it is, but that doesn’t mean you can never use the words “Final Cut Pro X” anywhere. We use it all the time on these forums, no one gets sued, it’s not illegal. It is illegal to profit from it. Stating you used it to edit a film is not profiting from it, as what NLE you use has zero bearing on its distribution. It is perfectly legal to say “Edited in Final Cut Pro X” and use the logo in ending credits. Over my long professional career twice this came up, and twice the legal dept said it’s legal fair use. So I’m not in doubt, I have no question about it, I know from actual lawyers, and from Apple internally (I have contracted work with them, I have good friends on the inside).
Plus, Apple is very well aware of how much it. benefits them to have this happen, they quietly encourage it, and the fallout if they sued an FCPX user would be a nightmare for them.