AOPA accident reporter gives some detailed "possible explanations" for catastrophic mid-air @ Dallas TX on 11-12-2022.

Keep in mind the narrator is a former flight leader for USAF Thunderbirds. Also, this is just a preliminary assessment of what might have happened. This is NOT a NTSB report or summary. That usually takes a long time.

Take a close look (use your pause control) of the P63 in the first minute of the video.  Note the windshield, corner posts, and forward cowling, the forward-downward visibilities are not all that great. Note how the pilot has to hunch a bit while taxiing. My personal feel is that he never saw the B17 making it's fly-by pass until the moment of impact due to the bank angle & radius of the P63 turn. The P63 has a 3-piece windshield with corner posts that contribute to poor static visibility. It's one thing to be able to scan & rotate your head while flying extended paths, but when you're in a 200 kt turn, you're probably looking to the inside of the turn, not the outward path. Disclaimer....I have never flown a P63. Even most of the now bubble canopy P51s you see had windshields that weren't built that way originally, they're modifications. Years ago, Smith Aircraft used to offer mods for P63s that were used in air races, but it doesn't appear the CAF P63 in the show had the mods, specifically the wrap-around windscreen. Also, if you're not familiar, the pilot straddles a driveshaft that goes under his seat from the Allison behind him to the prop gear case up front.  But, that doesn't have much to do with the problem at hand.

Here's the video by AOPA. 14 minutes long. Very good if you're interested in aviation. Once the dust settles, most pilots come out of the personal sympathy mood and want to know "why" also, regardless.

https://www.youtube.com/watch?v=rumZ1jc74f4