CrowdStrike is a EDR solution (End-Point Detection and Response) which is basically a Next Generation Anti-Virus Solution. While CrowdStrike doesn't explicitly have an Anti-Virus solution, it does have a HIPS (Host Intrusion Prevention System) which is very good.
CrowdStrike makes a very good solution, though I went with a competitor who is near the same standing, but substantially lower priced. Not to mention the other solution actually does also have built-in Anti-Virus scanning.
You do not have anything to worry about by installing CrowdStrike. Your system will actually be more secure by using it. Not less secure.