I checked on this due to your reports. "coreservicesd" was at 0% here running LR 7.4.2 on a Touchbar MacBook pro 15 (Mid 2017). Activity Monitor showed all processes at about the CPU levels you would normally expect, with the lanrev agent only at a usual .1% or so. I have 16 of these here on our site. There may be a factor extenal to the actual LR agent affecting yours. There were some reports from other LR admins that the download of LR was showing up positive for a virus of some sort. See the LANrev Slack channel for more details on that.
About 40 are deployed, antivirus (sophos) installed or not makes no difference. Only some of the High-Sierra-Installs have that problem, none of the Sierra-Builds do. I post this here also for those that are not on slack ;-)
You might try testing on a mac that has not only doesn't have AV, but has an empty folder at: /Library/Extensions/
You might have a 3rd-party kernel extension causing trouble--and that might explain why we aren't seeing the same things here.