I don't take the cameras out on the water, but I did during the snowboarding runs the last few years. I have both a gopro and an insta360. The gopro gives you more "professional" videos/POV vs the 360 but the thing I hated most about the gopro is you need a desktop to get the best editing features. The insta360 is much more user friendly and you can do so much more just from your phone.
The gopro has an iffy bluetooth connection to your phone and uploading can be a pain too compared the the 360.
The most difficult part about these two is that you can't really compare them. For action cam/POV/professional cuts, the gopro offers a lot, especially when you are looking to produce longer videos. Ideally, you need a few of them to get yourself in multiple angles so you can cut/edit to you heart's desire. But with new versions coming out every few years, the older ones are still capable. I currently have a gopro 10.
The insta360 is kind of a one stop shop for action cams. It's more for the short selfie action videos with a built in fish eye camera that gives you a 360* view and the "invisible" selfie stick is pretty awesome. I haven't used any desktop video editing software though so I can't really say how much potential it has. But, they have some built in features like "auto horizon" and "Point lock" which helps stabilize the image so its easier in post production. Auto horizon dramatically reduces camera shake and point lock automatically locks into whatever subject you want to focus on so you don't have to adjust what's in the frame during editing.
The gopro offers a 50/year pricetag for unlimited storage though and i'm sure the insta360 has something similar, but when you are cutting/editing on the fly, there's really no point to need a place to store everything. Both cameras are water proof up to 10ft I believe (insta might be a bit more).
Although probably not applicable to you, but gopro batteries are notorious for poor performance in cold climates. I have three batteries fully charged while at mammoth and they pretty much die by the end of day, where as the insta360 is good to go all day before needing a charge.
Also, keep in mind insta360 has a typical camera style screw in mount vs the gopro's "special mounting"
I suggest looking to go into the secondary market so you get the best deal, especially with the upcoming snow season. People will upgrade their action cams and typically will have package deals when they switch their platforms.