It's a tool, just like a DP. You wouldn't say to block and never DP.
By that I mean poking to get out of pressure, or using a counter or DP. Not just flailing desperately.
I feel like there is an evolving mindset when it comes to this.
Beginner ~> Mash desperately, get blown up by frame traps.
Mid level ~> Blocking good, pressing buttons bad.
High level ~> It's a tool like anything else, use it when appropriate.
This is actually a logical progression, because when most people start the game they have no idea what they're doing, so they will get bodied. To compensate, other players will tell them to just focus on blocking so they can learn how to play defense, so they gain control over their buttons. But eventually that player will learn that it's not all bad and that there are times when it's appropriate and even necessary to try and get out.
For a lot of people they act like just DPing out of pressure, or pressing buttons is somehow bad form and against the rules of the game. But it's only frowned on because the OTHER PLAYER is what causes the negative. You do it too much and you get punished. It's not inherently bad by itself. If the opponent can't enforce that drawback then it is all upside.
It's like playing Starcraft, and going for an early expansion. If the other player is never rushing or scouting you then it's a great move.
Plus there are some moves where you are put into a disadvantage just by blocking them, because it lets the opponent restart their pressure or go into some mixup.