Everyone has their own opinion, but as long as the airlines are hiring pilots who earn the majority of their twin time doing the safety pilot thing - pilots will continue to do it as its the most economical way to get your multi-engine experience.

As Rickair said, you do actually want to avoid IMC conditions since only one pilot can log time here and the cost per .1 on the hobbs goes up.

From an FAA standpoint, its safer since you have two pilots up there making decisions and working together.

From an airline standpoint, MEI time is great but its generally VFR stuff. Safety pilot time is generally two pilots flying IFR and also working on CRM (its more airline tailored). So yes currently it is accepted, who knows if it will not be accepted when the airlines aren't so pilot hungry.