Today, TVs are by nature not dumb, what make them a TV and not a monitor would be the presence of a tuner, and modern tuners are built-in computers that can at least decode compressed video, which is not a trivial task, especially at 4K.
The reason people don't like smart TVs is not because they have a computer inside of them with internet connectivity. It is because of ads and partnership deals. And of course people don't like it, because as much as manufacturers advertise them as features, they are not made to add value for the customer, they actually lower the value. But here is the thing: they lower the price even more.
Let's say a manufacturer makes a TV intended to be sold for $300, they reach for their sponsors and can get $50 of deals. Now they can chose to sell a "sponsored" TV for $250 or one without the annoyances for $300, and as it turns out, the majority of customers will go for the $250 option. So much that there is no good economic reason to even sell that $300 ad-free TV, the niche is too small. Competitors without sponsorship deals and $300 TVs will be out-competed by that $250 TV and will have to adjust. As a result, we all have the "smart TVs" we hate (but with a price tag we love).
Pros are ready to pay to avoid all that bullshit, but they don't need TVs either, they need monitors, that's why you can find monitors without that bullshit, for a price.