It’s an interesting point, and it would work well for small projects to upgrade constantly, ensuring there is little technical debt. However, in large projects, this constant upgrading might not be viable.

Surely, so far upgrading hasn’t been too hard, but there are breaking changes sometimes. This might not always be as straightforward as it seems. For example, platform setups might have to change (PHP versions), lack of resources, lack of budget (customer doesn’t want to pay for it, or there is no internal budget, company priorities etc etc.

In theory most things are easy, but in reality things might not be so straightforward.