Second doctor's outfit simply changes, Third Doctor could have regenerated those clothes that feels somewhat implied to me, a recent Big Finish story had a thing called Degeneration and outfits changing each time
Also Doctor Who is a weird show to be complaining about continuity.

The Doctor is a human from the future wait no a Time Lord Fugitive or maybe he is the founder of Time Lord Society (The Other/Seventh Doctor), Eight fought in the Time War never mind that was John Hurt but here is a new story about Eight ending the Time War after that retcon, The Doctor has thirteen lives and the Valeyard happens but then who are the Morbius faces and they are the founder of Time Lord society again with hundreds of lives but in a contradictory way to him working with Rassilon

I also agree it is a unique regeneration, in the modern era picking out the clothes is part of establishing a new identity but 14 is someone with other things to figure out, why this Doctor is back. So the clothes come with that. One could also say he stopped letting regeneration change his clothes once he learnt he cared about his presentation as an identity forming thing as opposed to letting Regeneration handle that