I don't think it's a big deal. If people understand what's being said or written then it's done what it's meant to do.
If that is true, why do people get angry with misspellings and typos on printed advertisements, wedding invitations, diplomas, trophies and newspaper stories? I'm pretty sure the general meaning is clear in all these cases. The reason is because it looks sloppy and careless, and makes a bad impression. We should all be held to the same standards.
We're talking about why the anger is justified... it's a huge jump to say there's some reason in the sky why everyone needs to be held to the same standards, and another one to say people should be angry if others fail to meet those standards. The errors don't cause any problem, the meaning was understood; people get angry over stupid stuff. And sorry, but if I'm going to debate with anyone it will be something that's worth my time, and I could learn something from, but not about whether or not we're justified in getting angry over spelling mistakes.
Linguistically, there is no misspelling or bad grammar.
Beyond that, to be offended by a variation in natural expression is a sign of misguided national spirit or philistine prejudice.
Let people pronounce and write the way they pronounce and write.
To think otherwise is to succumb to authority.
A bunch of thieves.
Before Shakespeare and James the vernacular was free.
Tick on. Do not tick off.
Embrace the world.
This sounds very convenient in a one world/I'm okay, you're okay/60s halcyon sense. How can you make a political judgement about misguided national spirit based on how some people react to others that can't be bothered to reach for a dictionary? I'm not interested in breaking people's balls unnecessarily, just valuing clarity of expression and precision of language over obfuscation.