The English language in decline?

A message (unlike that quoted here) that ends with 'inconvenience' rather than 'caused' has the listener or reader (this one, at least) bounding with joy (figuratively). Yet the chance to bound (whether figuratively or literally) comes infrequently, for 'the inconvenience caused' is almost as ubiquitous as 'to be honest', never mind 'you know'.

Then there's the use of language in circumstances clearly showing that the user/s believe the recipient/s are, bluntly, stupid. Thus, those messages arriving in an e-mail user's 'in' box:

'Dear Officers, Your mailbox size of 1 GB has exceeded its quota and we areperforming [sic] an ongoing upgrade in our Iprimus.com.au mailbox database, and we are de-activating all our un-used account [sic], so there can be enough space forour [sic] certified users.

'If You Want Your Mailbox To Remain Active, Then You Have to Provide YourCorrect [sic] Account Details …

'Fill the detail correctly for your account to be upgraded.

Name:

Surname:

Email address:

Password:

Confirm password:

Date of birth:

'… Thank you for your cooperation …'