[kccqzy]

Because they provide far more protection than Windows defender. You can write your own custom never-before-seen malware, and CrowdStrike will detect it purely based on behavioral signals. Windows Defender is still largely an antivirus solution.

[Peanuts99]

Microsoft's E5 offerings are a direct competitor to Cloudstrikes threat response products which is a lot more than just Windows Defender on endpoints. I'd imagine many of Cloudstrikes customers will be looking to move this to MS's tools instead as a result of this.