Sure about that? 
Define ‘pros’, by the way.
By the way, sometimes those, ahem, players are pros, for instance:
https://www.youtube.com/watch?v=-jenlSf2E8o
And if you mean the ‘e-sports’ scene, i.e. those guys regurlarly receiving personal invitations to rournaments and so on — you know, generally they don’t let just anyone in there. For some games like Gwent, so-called ‘win trading’, practiced by so-called ‘pros’, was more or less an open secret for the community, HS has had those ‘Big Streamers’ (including their supposed own version of ‘RNG’), invited entertainers to put on a good show and so on — it’s quite a showbiz in its own right. On the other hand, it doesn’t mean that letting some occasional random person in there is impossible — if it sells, anything goes.
On the contrary, see the next point…
But why stop there and not sell the ‘We ArE aLl EqUaL’ concept? It’s a powerful message — that anyone can be someone, any bozo can become a ‘Legend’ — no need to study, train hard and so on, like in chess, which is, by the way, extremely hard to monetise, unlike games like this: the more… ‘accessible’ to masses (simple and flashy is usually good enough), the better.
PS Think I might be repeating myself again, but gonna expand on that idea a bit more: in boxing, chess, tennis or whatnot, an ordinary guy has practically no chances against a ‘pro’, grandmaster or champion. In this game, any hillbilly can kick their virtual butt and feel good about it — isn’t it quite something?
Hmm… Gotta say, you’ve played Dr Watson for me: even if what you’re writing is… let’s say utterly wrong , your mistakes are illuminating, since correcting them can lead to some interesting conclusions — gotta thank you for that.
You know, HS is such a small indie low-budget unpopular game, that they payed Kasparov, so that he’d play it as an advertisement for the product. Something tells me it’s a bit more expensive than adding a couple of functions (‘Optimotron’) etc to the code.