And I have a spitball theory who wrote the anonymous tipster email to Apple. Here’s an MD5 hash of my spitball, for future reference, in case someone else names them first:

72ecce571403600a27e986d40c0155b2

@stroughtonsmith I believe there are 3 different resource limits (which have all existed since widgets started, but some got stricter in iOS18).
1) a 30MB memory limit while refreshing the widget
2) an archive size limit on the complexity of the swiftui view
3) an image resolution limit

2&3 seem to vary based on device/size and I believe are not specifically documented. Generally for #3 the limit seems roughly the size of a widget’s pixel bounds. So you have to resize down based on family.