Foundations is intended to be a return to the basics, making it easier for new players to really get a handle on building decks, playing different formats, and learning the game
Take that, Ulamog
Then Wizards started giving us 3-mana creatures that also let us discard and draw, like Tersa Lightshatter and Kiora, the Rising Tide
I heard stories of cards like Fortune Thief, Fathom Seer, and Brine Elemental that all saw a bunch of play before my time
Ultimately, whether Baleful Beholder should see play depends on the current meta and how well it synergizes with other cards in your deck, but if its abilities align well with your strategy, it could definitely find a spot
One, it gets +1/+1 for every other cat card you have in play