With a budget that high, and you having used a gopro as a dashcam, you have to be careful not having too high expectations to what you can / will get.
So you don't have to spend that much, not even half of that.
You can go, i must have 4K like my gopro, and there are 4K dashcams on the market, but i can not recommend any of the current models, i am hoping the #2 wave of 4K will be better.
ATM the best all round performance you get from cameras with the IMX 291 ( 1080p ) and IMX 335 ( 1440p ) sensors, and a range of brands use those, some with no updates or for that matter support, others that do try to make their product better after launch, and that actually listen to customers.
Regarding the SG cameras ( which i am affiliated with ) then i personally feel the extra price are worth it, it is not like that extra price translate to much better image quality compared to some other brands with much similar hardware, but i do think some of that extra go to hardware, and their excellent customer care and support are for sure also something i am willing to pay a little extra for too.
It is very easy to find other brands, even big ones, that have no way near the same level of support you get from SG, and of course a plethora of brands which will sell you a camera,,, and then you hear nothing more from them.
SG are also made in China, but not "unrestrained China" which we have seen so often with cameras and other things can go very very bad.