Many people faced the problem, that when processing the point clouds in Revit computer, it starts to lag, and if the computer itself is old, then working on it will become unbearable. Luckily, if performing a small setup, weak-working machines can also deal with the given task.
1) Disable snap to point clouds
2) Install the cloud into the required place, and align vertically. Yes, it can still be lagging here, so you need to keep patience.
3) Lock the point cloud.
4) Disable selection of pinned elements.
Yes, in this stage Revit will start working much faster. If the lagging still continues, then it is necessary to increase the productivity of the computer itself. You can read about that in the following article.