No, It was obfuscated since around 1.8 when you (Microsoft) buy up Mojang Studios. before that? meh, It wasn't. That's the main reason why JE has broader mod ecosystem from the start., result being 1.7.2 being the one of the most active modded versions since most of them can't get passed to around 1.8.
The motive behind this is probably due to them finding out people can not get their mods/server software updated in-time (due to extra work required) and this leading people being really reluctant to update their versions.