Especially since 2016sp1 when they unlocked a lot of previously enterprise edition only features in standard edition. The scalability is still locked down a bit but those limits have crept up over time also: there is a lot that you can do before 128Gb RAM & 24 cores spread between up to 4 CPUs becomes limiting (core engine only limits there, OLAP services, reporting services, and the mem-optimised engine parts have extra limits on SE compared to EE).

Also a chunk of enterprise licensing is in support which if you are truly at that scale might be worth paying for. But if your company/product isn't there yet that is a cost worry to put off to the future, and as developer edition (which feature-wise is enterprise edition, you just can't use it in production) is essentially free you can test in advance to see when/if that expenditure is going to be worthwhile.

Of course it doesn't beat Free on price, so if postgres has the features & support you need, which for many it has, then it is far from an open/shut case. But compared to the other commercial products in the same market...

> it's been an absolute rock

Agreed. I can't think of another product that I've used nearly as much which has caused us so little hassle over the time. It certainly hands MS's other products their arses in that respect.