They have a windows 10 builder tool that downloads the ISO and burns it to USB or DVD. So there's not much stopping a customer from registering and then doing a crapware-free clean install. The downside (besides needing the skill and time to do it) is you'll lose any baked in freeware but the line between freeware, trialware and crapware is so thin now I'm not sure that's a concern.
Finally you can rein in the data collection and remove much of the microsoft freeware by using https://old.reddit.com/r/tronscript.