If the modder cares about compatibility, load all the mods he or she cares to be compatible with and call OreDictionary.getOreNames(), and if they want to go even further, iterate over the string array that it returns to call OreDictionary.getOres(oreName) and get a List of ItemStacks.
Mod compatibility is meant to be global, not something restricted to certain mods. Guess what forge does, by allowing several different mods to run together, without any problems?
Standardization of oredict names allow cross-mod compatibility between mods even if they don't know the existance of each other, so the end user will never find incompatibility issues of items of the same type if both mods follow the standard.
So, this is not something unnecessary and not making mods follow the convention will eventually cause item incompatibility issues between mods, like GT and TiC rods are incompatible because of different oredictnames for same item.
In the example you list, GregTech chose to not use the names that were already in use. Also, the code that GT uses specifically ignores a large number of entries that do not follow the guideline, such as bronzeTube, ironTube, obbyTube, leatherSeal, and stoneBowl
Bonus fact: one of the entries in the list of specifically invalid names is in fact appropriate according to the guideline: woodRod. According to the guideline: "- For anything wooden, please use "wood", then the type"