Having played Magic The Gathering in my college days, I have to say the game still remains tried and true to what I remember it being. The overall card game is still as strong and interesting as ever, and it even has more robust art now then it ever did when I played it.
Arena, however, is not the card game and certainly doesn't take up it's place, but it does a stellar job at bringing it to the digital world. For card games, a good understanding of how the game works is important for both players to understand in order to enjoy it to it's fullest, and Arena makes sure to do it's best by providing a ton of helpful tools and UI that readily tells the user what is happening on the board. The game also boosts a little training tutorial that explains the game in sort of mock battles which give players the ability to play through a per-determined game to see if they can win it with the cards given. Anyone mildly familiar with how to play card games will have an easy enough time with this, but new players may struggle a little before being able to access the rest of the game. As well, the game won't let you play Player vs. Player matches till you finish one of the color challenges, and for people that know how to play the game already, this can be a major hassle.
The shop in Arena certainly feels a bit predatory akin to most gacha game formats. It even has a bunch of skins and nik naks that players can invest in that makes me kinda cringe at the thought of recommending it to anyone that as mild gambling addictions, but the nature of card games kinda already lend themselves to such behavior. At the least, Arena proves to be a nice digital replacement for the table top game, and for spacing purposes, may be better for the average person.