Software development is just one piece of the bigger picture that your manager is concerned with, same way as adding features is just one among your many responsibilities.

Managers understand risk. Communicate the risk of disregarding bugfixes, documentation, technical debt, even if it takes a lot of handholding. Expect no less from your manger: if they can communicate client expectations, budget constraints, and most importantly: long-term strategy, together you may be able to devise a better plan to address your own concerns.

In other words, empathy can go both ways.

And yeah, there are bad managers, just like there are bad coders. Sometimes it's an interpersonal problem. It's called life.