I don’t have a different class fantasy but I realize it’s a different game and style of play. I would say that a problem with one solution, I.e. you have to have knock memorized is a poorly designed problem and I would say that a whole bucketload of early d&d modules were poorly written because it wasn’t until much later that they even figured out that was something people wanted to buy!I think it all comes down to playstyle and what a player wants in their class fantasy.
For me personally, when playing the older editions I never liked the fact that I could have a spell that would help us solve a problem in the moment, but because I didn't memorize it in the morning then we couldn't use that solution. The game was basically taunting me by acknowledging I have the answer, but not letting me use it. And the only way for me to use it was to guess at the start of the day that this spell might be a solution I would need and then cross my fingers it would end up being true. But if it turned out the entire day was ending up being just one combat after the other and half my spell slots had utility magic memorized... then I'd cast the few spells I had and then spend the rest of the adventuring day firing a crossbow and getting like one out of every eight shots actually hitting. Which is not how I would envision a Magic-User actually behaving.
I would imagine that you have a different class fantasy and what I describe above for you would be a boon, not a flaw. Likewise if I was to say that I actually love attack cantrips because it allows me to actually be a Magic-User all the time and not have to spend 90% of my day as an inept crossbowman... you might say that the proliferation of magic in the game has now made the game worse.
Neither of us is right, and neither of us is wrong. It's all just a matter of preference and perspective.
I also don’t have a problem with cantrips or flexible casting in general. I love 5e. But I also love 2e (1e kinda.) They create different play experiences but they’re easily my two favorite versions of the game. To me, it’s like saying driving on the left side of the road is weird - well, no, it’s just a different country. You get used to it. Every game system has it’s idiosyncrasies.