Being deliberately obtuse about that is not making your case.
I'm making a point that you're ignoring. The foundations you think the Timeless Child has shattered were not in place in 1963. The Doctor's background and character were developed in bits and pieces over the years. The Doctor is a strange person who travels through time and space in a box. That's it. That is the foundation of the character. That is untouched and unchanged.
Also, who says I like the Timeless Child? I'm intrigued by and open to the concept, but the story still feels unfinished, questions unanswered, and I hope for a bit more context for Jo Martin's Doctor, among other things. I'm not convinced how well it works, how well it's been thought through, but I'm open to it all because there it is on the TV screen. It's part of who the Doctor is now. I'll watch and see how Chibnall winds it all up. In the long run it's not likely to be any more important than the existence of the War Doctor or the Doctor being half human. If Davies and whoever follows don't like it, they'll do what every Doctor Who producer has done: tell the stories they want to tell and use the parts of the past that appeal to them.