It depends on the person and their financial situation.
Something like a 25% tax on a console that costs $500 normally would bump the price up to $625. Even a $400 console suddenly becomes $500 with that tax. In your example, the $600 PS3 would become $750.
For something that is a luxury item marketed mainly towards a younger audience, even $100 can easily be a tipping point between "buy" and "nope."
How old would you say the average gamer / maga douche bag is? And how eager are they even going to be to upgrade presumably in the fall of 2020 when these systems are slated for release? Generally, it takes around 18 months before anything good is ever released on new systems. I didn't bother to open my PS4 until Arkham Knight was released, and I purchased my PS4 when it launched in the fall of 2013.
I'm fortunate that I can weather this storm. That's also the impression that I've been getting here from a number of other posters on this forum. A bit of schadenfreude under the blind assumption that these dipshits are somehow going to get irreparably screwed over by this, which only works if they're financially unable to make these purchases.
Whether gamer gaters end up getting scorched or not is immaterial. Everyone is getting screwed by this development.
I haven't been paying attention to 4chan or reddit. What is the sentiment there? Early adopters who plan on upgrading both Xbox and PS5 can now look forward to forking out close to $1300.
Also...
When will the retail prices be made public? And how close will this announcement be made during this election season?