The way I understand it, the underlying simulation platform has to support it. MSFS currently doesn’t. Knowing that PMDG is working on the 737NG v3 for MSFS, I know it will happen eventually. However, currently available third party aircraft, i.e. the IndiaFoxtEcho T-45C, have HUDs that can’t be collimated because of this issue (confirmed in a post on the IndiaFoxtEcho Facebook page). That HUD IS correctly collimated in FSX/P3D. As mentioned by others above, even the stock 787 HUD is a mess.
I know this isn’t an important issue for most MSFS users because they either don’t fly HUD-equipped aircraft in MSFS or don’t understand the problem (I’m guessing both are equally valid). I fly a HUD-equipped jet in my real life job so this is an important issue for me. It also pushes the realism boundaries in MSFS which ultimately benefits all of us.