@rebbetzin- “Is that not the same with those that use cholov akum – how many actually researched the issue (or even looked up Reb Moshe’s teshuva) before they decided that they can be maykil?”
How many learned the halochos of eruv in a metropolitan and examined the eruv of their city before deciding that they can use this eruv?!
Get real: we ALL rely on precedent!”
Using Am Horatzos to excuse precedent is a silly thing to do. The assumption people among the right make is that the precedent set by their Rabbonim is one which abides by Halacha. The precedent held by the MO (and more particularly, the type of MO who wear pants, don’t cover hair, etc…) is used as an excuse not to keep Halacha. To conflate the two perspectives is disingenuous.
(Additionally, the examples you gave aren’t really so much of precedent- when you rely on an Eiruv, your basically relying on those in charge of the Eiruv, i.e., that they know what they’re doing and they have who to hold by. Rav Moshe’s teshuva about cholov hacompanies [which is also dangerously close to the heter used in Eretz Yisrael by tnuva mehadrin under Rav Elyashiv’s shittah] is also not an example of one relying on precedent- rather one relying on a psak. They may not know the in’s and outs of each psak- yet they know it exists….)