UTFT supports known "models" of screen from known display sellers.
Please note that may Ebay, AliExpress, Mcufriend, ... adverts and descriptions are often mendacious.
I would be fairly confident that you do NOT have an ILI9488.
Life is much easier if we could see a photo of the actual pcb. We can pick up a few clues from the components, copper traces, printed legends.
All the same, everything is a bit of guesswork. But with accurate answers, I could probably identify the controller.
Your screen is clearly "MIPI compatible controller" because it obeys the setxy() commands.
All "MIPI" screens obey the basic User commands.
The Manufacturer commands differ between makes and model of the actual controller Silicon chip.
0x36 is the User Memory Access command. You will see that the "new" initlcd.h sets bit6 (MX) which controls the X writing direction.
As long as you get a correct picture in a single orientation, UTFT will do ecverything in software. e.g. Landscape.
Mr Karlsen is only prepared to support certain screen sellers. TFTLCDCyg's ZIP obviously works for your screen. It seems to be hacked from UTFT v2.8.1. The current UTFT is v2.8.2
Personally, I would be much happier with accurately determining the actual controller mounted on your screen (not visible from the pcb). It is possible to do this by observing the behaviour of different Manufacturer commands. Incidentally the 0x36 User command has some differences too.
UTFT was not written by me. You would need to ask Mr Karlsen for any official changes to UTFT.
David.