Obviously players that walk are good, players that hit for power are good, and players that do both are doubly good.
Toronto was and is in the market of trying to acquire low-cost players with upside. In the modern game of baseball, one way to use fancy stats to sift for gold is to acquire undervalued players with nice exit velocity stats. The theory is that with some adjustments (launch angle, etc.) raw exit velo can be channeled into offensive production.
It's possible to teach a powerful hitter to be more patient. With experience they can learn to lay off outside pitches. Or, as they become more establishes pitchers will pitch around their power more.
It's very hard to teach a low power hitter to hit for more power. High BB% players are very much not a market inefficiency anymore; every team knows that outs are bad. There really is not a viable rebuild strategy in the modern game of baseball that involves going out and acquiring players that like walks. It's just not an efficient metric to focus on. There aren't much gains there.
It's kind of a chicken and egg thing. Sometimes, a nice batted ball profile can indicate that a player has the ability to develop into a good hitter who also might have a nice plate discipline profile. Sometimes players with nice batted ball profiles are available for cheap because their approach, or luck, etc. has lead to poor production. It's less likely that players with nice plate discipline profiles will be available for cheap because a) they might already be good or they probably have highly regarded hit tools. It also might not follow, at least not as often, that nice plate discipline profiles will indicate that a player has the ability to develop into a powerful hitter (although this has happened historically, you could probably find examples).
Regardless, a lot of the bats that Toronto is developing seem to be capable of taking walks so I don't think this really matters as far as Toronto is concerned. You're basically just pointing at 3 or 4 players on the current big league team who happen to hack away (Grichuk, Teoscar, Gurriel...).