I used SOAP (Simple Object Access Protocol) extensively between 2000 and 2005 back when WSDL remote web services were beginning to appear providing stock quotes, weather, news feeds, and so on. I guess SOAP was "simpler" than CORBA (Common Object Request Broker Architecture) but it was still far from simple, and like CORBA, it was largely based on the remote procedure call (RPC) paradigm which I never really liked. (Nested RPCs can get very messy and lead to deadlocks.) One particularly sticky point with SOAP was dealing with RPC/literal vs. RPC/encoded vs. Doc/literal. Unfortunately, I've been needing to deal SOAP as late as 2019 in the form of EWS (Exchange Web Services).
Experiences using this skill are shown below: