There's no chance the devs will ever implement a toggle for players / guilds to opt in or out of using datacrons, as you've suggested here for GAC / TW. Players who choose to invest their time / energy / crystals / cash in these things are doing so to gain an advantage over those that don't. I don't understand how anyone can think the developers would make it so that players who do invest in something like datacrons would be "rewarded" by only facing others who do the same.
I don't understand your point about PvE omicrons (Raid omicrons and your Carth mistake aside). There are 2 conquest omicrons and I know more than a handful of forumers who have cound POW's omicron in particular to be game changing in Conquest. I haven't applied it, but over 69,000 others have.
TB omicrons can also be very useful. I've only applied two (Marrok and one of JKCal's), but I have zero regrets about either of them. I know of many players who swear by them for the assistance they give in the most challenging PvE game mode.