Well, the web (most common frameworks) doesn’t really have drag’n’drop UI editors. Writing complex widgets for the web had a long list of issues for a long time and only recently became feasible without hacks (they couldn’t be reasonably encapsulated from the rest of the website before shadow DOMs, and better js encapsulation).

As an example, there is no standard, no-one-gets-fired-for choosing complex table widget that can sort, filter, paginate, re-order, etc its rows/columns. Many of them fall just shy of a prod-ready implementation.