Right exactly. The strongest are the ones who have the longevity to have lots of kids and reproduce themselves.
Right again, part of the problem with evolution is that it often ends up making situations where there is TOO perfect a match. That combination of creatures works so well together that other version that are less perfect die out, there isn't enough food for them. So before there were a variety of different bees and some were better and some were worse at this task. The ones that were worse died out. So now there's only one remaining type of bee. If that bee population gets hit by a virus, game over. The flowers die. So it would have been in the flower's best interest to be more general - to appeal to more types of insects. But unfortunately flowers don't think like that

They just think "this is really good! I like this combination!" and focus on that survive-to-the-next-generation issue.
I suppose it's like tigers. Tigers evolved over a ton of time to have stripes that matched the grasslands they lived in, so that the patterns of stripes gave them perfect hiding potential. Those tigers that didn't have stripes or that had different kinds of stripes were spotted more easily, and didn't get their mouths on much food. So over the years tigers have managed to match perfectly with this style of jungle and grassland. But what if a gigantic fire struck and wiped out all of that jungle and grassland? Now the plainer tigers would be the ones that survived - the really stripey ones would stand out and never sneak up on any food. So we'd see an evolution of plain colored tigers, maybe tan tigers. The stripey ones would die. That's just the way things go ...