I think people have been burned by RxJS where observables are "cold" by default and the source of many problems, over subscriptions, false starts etc. The mode

I think people have been burned by RxJS where observables are "cold" by default and the source of many problems, over subscriptions, false starts etc. The modern swing back to signals (which in a way stem from Knockout's observables) seems to be simpler and easier to reason about.