Microsofthello BertJansen,
In the original post, you say: "believe Microsoft 365 customers will be better served by modern SharePoint extensibility models". Can you please provide more details on how exactly modern models better service customers like myself who build enterprise data security solutions on synchronous RERs?
I've already commented in Remote Event Receivers retirement update in SharePoint Online - Microsoft Community Hub, just joining AllanJuncherPedersen, M1980, MatthiasIwer, SteveBeauge and other participants here. Retiring a well-established proven solution without visible security and performance implications and replacing it with an inferior one which obviously failed to live up to the hype is a very questionable move which will definitely dent trust in Microsoft among enterprise IT professionals quite a bit.
I have no problem with learning new skills and methods, the issue here is that Microsoft are not providing any alternative to synchronous RERs at all.
