Definitely don’t t-cut it!
If you google, caring for matt paint, there’ll be loads of info from detailers and the like. This from autoglym,
https://www.autoglym.com/blog/2017/0...aint-finishes/
If your serious about future protection........ ouch, the price!
https://www.cleanride.com.au/opaque---matte--satin.html
A video
https://www.youtube.com/watch?v=FPlP1q-cC1w