Arguably, the Mediator pattern has become cool among the .NET devs when Jimmy Bogard released MediatR library 4 years ago. That library made words "Mediator" and "MediatR" interchangeable in the devs' lexicon. And as usual, trendy tools get often misused and applied without a second thought. Here I'm playing devil's advocate and look closely at its pros and cons. Is it still useful for modern .NET projects? May it become an anti-pattern one day as Service Locator did?