I agree, but only partly. Yes, prioritization is likely the explanation for a lot of things. It's absolutely true that the responsible team cannot do everything you'd wish.
But, sometimes there's stupidity at a different level. Just because someone is making an effort at prioritization doesn't mean they are doing a good job of prioritization.
It's hard to tell from the outside (where you lack the relevant knowledge), so you're kind of forced into giving them the benefit of the doubt. But sometimes that internal tools bug which they never get around to fixing is eating up 5 minutes of every employee's time every day for 2 years, and it adds up to a lot of wasted time, and they should have prioritized it but they didn't. Maybe because they didn't appreciate what the cost was, or maybe because they had some bias toward certain kinds of tasks, or maybe some other reason.
But, sometimes there's stupidity at a different level. Just because someone is making an effort at prioritization doesn't mean they are doing a good job of prioritization.
It's hard to tell from the outside (where you lack the relevant knowledge), so you're kind of forced into giving them the benefit of the doubt. But sometimes that internal tools bug which they never get around to fixing is eating up 5 minutes of every employee's time every day for 2 years, and it adds up to a lot of wasted time, and they should have prioritized it but they didn't. Maybe because they didn't appreciate what the cost was, or maybe because they had some bias toward certain kinds of tasks, or maybe some other reason.