I would offer a counterpoint: most software in existence was written by not-software-professionals in Excel (most likely poorly).

Within reason I think there is a rational basis for not having to involve software engineers for every project - especially if the SMEs with understanding of their requirements are the ones building it.

This will probably fall over in the same space as Excel spreadsheets do though, when the domain complexity outgrows it, way before anyone is able to recognise that.