Yes, this issue is still present for Macs with high res screens. It's very frustrating for a large number of people. The AE team has said they are working to address it.
You can either deal with it or use CC 2014. Both of which are really frustrating choices. Hopefully it will be fixed soon and this won't be an issue.
Everybody who is having this issue, please install the latest update that came out last night: After Effects CC (November 2017) Bug-Fix Update Is Now Available
This update is 14.0.1 and should be a bug fix for this and several other disturbing issues - especially for Mac users. It does not fix all the bugs that are new with the CC 2017 release (Known issues in After Effects CC 2017), but it does fix some issues that have been plaguing After Effects since the first parts of the new architecture showed up in the CC 2015 release.
If you can't see the update yet, you may need to wait a while until you see it as it can take up to 24 hours to populate an update across all the data centers. You may need to log out, relaunch the Creative Cloud app, and log in again.
Hahaha! Thank you for letting my know so promotly. I have a new major project to commence and I really wasn't looking forward to wrestling with this. So I'm definitely updating for sure! I'll let you know the outcome.
Hopefully it works!