My Significant Locations list has always been set to off and I usually advise privacy concious people to switch it off. With a new iPhone it's always a good idea to go through all the settings and make sure it's all setup the way you like it.
"When you turn off “location history” Google still tracks your location when you use several of its key services including Maps, search and the weather. Here’s how to really turn all of it off..."[0]
[0]https://www.theguardian.com/technology/2018/aug/14/how-to-tu...