Amen <3
if every author that made a ui (not addons) only posted unique ui's there would be hardly any, as you ask anyone thats made anything,
even Tuk that made tukui
Everyone has elements or has taken inspiration from someone else's creation
Elv, Tukui took "Alot" of inspiration from Caith ui,
it even says in the credits inspired by Caith,
and if you look through all 333 pages here, you can see many people have taken insipration from other peoples ui's this does not make them copy's as there are different they just took a good idea and tailored it to there own liking,
other examples
Armani t-shirt,
Nike T-Shirt,
there both the same only difference is the design of the logo. there still based off the same thing and they are not unique yet they are both available on the shelf to buy,
100% agree with Lyn here