Well, MTG Arena is changing that somewhat, but we will see.

HS's problem is that their model just needed to be better than MTGO at that time. So, their pack cost/value was modeled after MTGO, and they created a F2P aspect that was ok at first, though would be extremely grinding to do today. Keep in mind that MTGO was outdated by about 15 years when HS was setting up camp to simply do a much better job than MTGO (a very low bar, if you see what I am saying).

I say this having played HS from the day they released it. Credit is DEFINITELY due for Blizzard creating a UI and a decent F2P model to get us out of the MTGO tarpits. Eternal, ESL, SV, and most others are all copying the UI idea Blizzard started. So, don't think I am knocking HS. I am just trying to be realistic.

Just about everyone you ask who plays/played MTG or MTGO competitively says the cost between MTG and HS are about the same. If you compare pack to pack cost/value, MTG packs actually cost a little less, and give you more card value, especially because of resale value for rares and legendaries. A modern CCG cannot cost even close to MTG or MTGO is they want to survive. They are only offering gameplay, not value for cards owned. So they have to be cheaper.

If HS started rewarding 50 gold and a pack for three wins, and went heavier F2P, they could stay competetive. But the route they are on now is turning people off, and they have started seeking out and playing other games, like Eternal.