what type of personality is big tech grooming its users to have?
The intellectual equivalent of obesity.
People often offer this line of reasoning up but I have always found it lazy. "They want us to be obese", well no, they want you to consume the product, and they'd prefer if you continue consuming the product, but whether or not you are obese is irrelevant to the machination.
de-politicization (whether its through sportsball/looksmaxxing/drugs), isolation, mental illness, weird kinks and poverty.
That's the path we're on right now
Big tech and big tech enthusiasts have always been very spiritually devoid people. It's hard to put into words, but there's something that fundamentally makes sense about a natural progression of basic high schooler pushed toward STEM tracks --> college major that requires few humanities courses --> STEM job that sparks absolutely no intellectual curiosity or respect toward humanity. The products produced by big tech and the culture perpetuated by the employees and tech enthusiasts who haven't read a book since they were 18 is just endless progress.
I also don't think it's anything intentional. Big tech prides itself in removing as much humanity as possible in the name of constant efficiency and progress. The average person has no problem with this because they also never read a single assigned book in high school. So the consumer already lacks any sense of philosophy, and the enthusiasts and employees lack the same, and so big tech itself lacks it and makes products that lack it to sell to the consumer.
Overall, big tech isn't grooming anyone. The makers and the purchasers both already lack spirit. Probably when university started being seen as the natural "next step" from high school rather than for people truly interested in pursuing knowledge of something. Universities and the school systems had to start performing as businesses that offer diplomas rather than actually trying to teach something.