I would like to fix these issues but many things are difficult or impossible and the available solutions have drawbacks. As far as I can tell these are the issues which are bought up.
These issues would be fixed easily if the engine was able to split things which have completely different behaviours but depend on the same thing. There is one tag for unit radius and center point which controls projectile collision, unit decloaking and unit selection.
Issues1. Nanoframes decloak.This would be nice to fix because the tactic is unsightly but ultimately I think it is a low priority issue. There are many ways to decloak things in areas that you safely control so it is not much of a balance problem.
2. Nanoframes block unit movement.Units can kill nanoframes so I am not sure how much of a problem this is.
3. Nanoframes block projectiles.I would say this is the most pressing issue and probably the easiest to fix although many fixes have drawbacks.
SolutionsA. Nanoframe decayThis was removed years ago because it enables reclaim with no BP spent. Additionally it is annoying to leave a constructor with Wait enabled to prevent a structure that you want to go back to from decaying. This somewhat fixes 1 and 2 except if you get a nanoturret to wait-poke all nanoframes in it's radius. 3 is not particularly affected because you can make frames when you need them. Implementation is somewhat complicated by terraform.
B. Nanoframes don't exist for the first X metalAfter X metal what happens if there is a unit, or even a structure, in the way? Additionally an invulnerable unit for construction cannot be right clicked on to produce it as everyone knows from terraform blocks. Technically this solution is possible because terraform blocks are already nanoframes which have absolutely no effect on opponent units.
To fix my first issue with this solution the nanoframe could constantly check after X metal whether the buildspace is free and then allow construction to continue. This requires AllowBuildStep which is a large source of slowdown.
Invulnerable nanoframes for the first X metal makes turret push more powerful, especially LLTs and MTs if you can make an LLT which pops in able to survive some defender shots.
C. Nanoframe hitvolume rises upwards for the first 33% of the buildThis makes a lot of sense give the building animation but has similar, but not so extreme, selection issues to solution B. I think this would solve issue 3.
If 1 is fixed then 2 is a problem because nanoframes built as a wall can stop ground based cloakies.