Avoid enormous network payloads with a video on my home page banner

I have a website with a video on my homepage banner that plays automatically when the user gets on the page. Google PageSpeed Insights is complaining about the video network load because of it. I was wondering how I could avoid getting this message. I was looking at this website : https://www.leclosdamboise.com/ They also have a video playing (40mo) but do not get the "Network Overload" error message on Google PageSpeed Insights. Anyone has any idea how they do it? Thank you