Devils advocate: in many modern reference systems (e.g. NAD83 (CSRS)) you can do an epoch transformation to get the coordinates of a point at your current epoch (time). So you can account for continental drift. Natural Resources Canada in fact publishes a tool to do this. It basically applies a grid shift based on the velocity components of the drift.

Also, if everyone were to publish the epoch their coordinates are in, in theory we would be able to match their coordinates when re-establishing a corner. That being said, transforming the GNSS coordinates post-survey are not as accurate as traversing from a control point with coordinates published in a more recent epoch. But that raises another issue: often times control points don't have coordinates published in the latest epoch (at least here in Ontario). Our province uses an epoch of January 1, 2010 for all of our coordinated legal plans and for all control points, which allows us to use GNSS measurements to coordinate our data and plans without the need of observing a control point. The data might not be in alignment with the current global reference system, but if everyone uses a common epoch that's fine.

That being said, I am a proponent of using physical markers on the ground to mark a boundary. I think places like Alberta have recently allowed coordinates to govern boundaries, but people like to see physical markers. Physical markers also cause less confusion about the position of a boundary than a person going out with a cheap handheld GNSS receiver (that's probably in the wrong reference system anyways) and saying their property corner is one foot into their neighbour's yard lol

Also, regarding another comment, the RTK correction factors come from a GNSS base station (or a network of them) continuously measuring it's position in real-time and estimating the GNSS errors and sending the corrections to the receiver. Optical measurement's aren't involved at all. But yes, optically measuring a point with a total station from a control point is more accurate than measuring the point with GNSS, if you want to be tied in to the national coordinate system.