No, the rules aren't any tighter now than they ever were, it's just that with the info easily available online more people (on here) are aware of them, combined with more mail going by air rather than by train, as I said above, RMSD will now routinely travel by air which means it gets Xray'd.
A lot of people post anything & everything without the slightest idea that certain items are restricted or prohibited, other people, that do know, lie (or are less than truthful) about parcel contents.
Re insurance, plenty of people pay for extra cover without understanding that their item is excluded & limited to the basic level of the service they pay for
but unless they're unlucky enough to need to claim they live on in blissful ignorance thinking they are fully covered
99% of the time there will be no issue, a few people have however been unlucky.