I have no doubts Artifact is "inspired" by Hearthstone. success, and I have no problem with it. I mean, imagine if the only shooter we had today was whatever came first.
But the list of games trying to ride Hearthstone success is big and yet none managed to topple the giant. Different from Overwatch or even WoW at the time I don't think Hearthstone is the best in the market. The client is buggy and lack basic features and at least for me, doesn't feature the best art in the genre.
So why Hearthstone keep the lead? Outside of the investment factor of people not wanting to start a collection from scratch, I think Hearthstone is easy. Every time I see a new card game they have some feature like multiple mana colors, multiple lanes, hex grids and whanot.
On other side with Hearthstone lots of decks can be auto-piloted and while you can obviously misplay usually the best options are pretty clear. Mysterious Challenger turn 6 anyone?
From what I saw so far Artifact looks a step above Blizzard's game in difficulty so I have my doubts if people who are used to that laid-back approach will enjoy a harder game independent of how good it may be.