I agree with you, but he could have said "I honestly don't think you know enough X to be really useful for Microsoft."

The friend said "No loss for Microsoft", showing that he cares about Microsoft.

A real friend might have said "From my perspective you could improve as a programmer. Your weakest point is field x and therefore I recommend that you read the following book."

I don't think so in the general context, unles the relationship is close and you can say anything to each other without hurt feelings.

Saying a person sucks is pretty pointless without a detailed performance review, identifying a few key points to improve in the next span (of months/years) and keeping tabs on progress. Usually saying someone sucks in general is pointless demotivation and hurts feelings without purpose.

Identifying specific sucky aspects in ones work and suggesting helpfull improvements is beneficial, if requested.

I think the OP knows that he isn't all that awesome at programming. As a friend, I don't go around pointing out to my friends weaknesses in their person they them selves are well aware of. In this situation the friend could have said something like "Oh, that's a good idea that you passed on that job, you are week in that area, and they were probably looking to hire you as a sacrificial lamb." A statement like that shows that a person is your real friend. They are acknowledging your weaknesses, but with the goal of helping you in the end of the day, not the company.