Which works entirely fine in most cases. You're at greater risk of phantom reads and general "stuff that can occur while you hold open a transaction", but if you're not handling that correctly then you're not handling that correctly. It's only a matter of volume, not existence.

... with a clear exception for cases where you do need to truly end a transaction, like if you're relying on some other thread to do something on a different transaction that needs to see your changes, or when you risk a deadlock somewhere due to not releasing your lock. Those are both a risky patterns for a lot of reasons though, and worth avoiding at design-time if at all possible.

I do not know why that mentality exists in the industry, but I see it all the time... for the past 35 years.

Combining that with spaghetti that does transaction magic at random places guarantees the sort of pain that makes cursing the entire human race seem like a pretty mild response.

Higher-level abstractions may prevent some footguns; e.g., an “atomic” decorator/annotation commits automatically after a successful call. They are somewhat easier to understand but come with their own limitations and caveats.