This is a recurring theme that has been explained again and again ad nauseam...
It has already been shown that, according to an Activision patent used in every Blizzard game with the simple objective of increasing revenue, the matchmaking and everything that should be random in the game is in fact rigged, there is nothing truly random in Hearthstone, but everything is performed by an algorithm that, for example, automatically chooses your opponent based on your winrate and the type of deck and cards you are going to play with, or even is able to alter the odds of drawing a certain card at a certain time or chooses the best or worst option from a pool as it deems appropriate.
But why? What is the reason for this algorithm? It is very simple: when you go to play a game, the algorithm used by Blizzard has already decided beforehand whether you should win or lose that game: your fate is already sealed. According to Blizzard, in theory, this ensures the ideal 50% winrate every time for everyone.
The problem are the usual fanboys who refuse to believe the evidence and charge against it, trying to make it appear that everything is our imagination, a coincidence, that the holy Blizzard would never put its financial interests first over the interests of its players.