No, difficulty can drop. Miners strive for an average of 6 blocks solved per hour.

EDIT: reading your post more carefully: the system is designed to go up in difficulty with the amount of mining going on.

Mining success depends on the current difficulty rate.

My understanding is that miners do a check every two weeks on how many blocks were solved, and adjusts the difficulty to reach a consistent rate of six blocks per hour. Mining can be worthwhile when either the price of btc are high or the difficulty is low.

This is only partly correct. While you can generally trust a self signed certificate to establish an ssl connection, haphazardly allowing the self signed paypa1.com to get the immediate go-ahead from a browser is a terrible idea. The warning pages are essentially asking users: are you sure you know what you are about to fucking do? If anything, browsers are too lax towards established certificated authorities.

It would be impossible to just create all btc at once, out of thin air. The process of generating new blocks is so mathematically intense that it requires a distributed network comprising tens of thousands of computers. I can't say if it's more efficient than the energy costs of running the credit card industry or the money printing industry considering all factors, but then again I'm not entirely sure bitcoin is designed to be green. It's more of a pseudonymous commodity market.