Yes - these serial numbers are there for a reason. They identify the batch no. of the product, time of manufacture / packing etc. This means that they could identify the production line / vessel / machine or even the shift that produced the item - not just the date of manufacture.
Would I drink something that was over a year old? Yes, I had a nice drop of Bordeaux the other week that was a 1986 vintage. I have some wines in my cellar that are nearly 40 years old. Perhaps I should throw them out now?
Having seen your related question in Law, you obviously do not understand the difference between Sell By date and Best Before date.
'Sell by' dates are used on perishable goods where deterioration could be harmful, eg milk, meat, fish which 'go off'. It is an offence to sell goods after this date as they would be deemed 'unfit for consumption'.
'Best Before' dates are use on dry or tinned goods where, over time, the product may lose quality, such as taste or texture - but don't actually become harmful if consumed after this date. It is merely a guide.
Canned and tinned goods (such as your can of Diamond White) will keep for a very long time (many years) with very little deterioration in quality.
So, unless your can was damaged or punctured, it is extremely unlikely that it made you ill because of the contents being 'off'. Perhaps you just can't handle your drink?