I ll tell you in a simple way why it does not protect you.
When you inject more steem into the system it makes your money worth less
No it does not, and this is the source of your confusion.
Let's use another example here. I have 10 coins, you have 10 coins. Now we create 20 coins out of thin air (100% inflation!) and give you 10 and me 10. Has anything changed here? No.
As I said earlier, this is a stock split dynamic, and does not change anyone's purchasing power, despite that scary "Inflation!" word.
Steem is a little bit more complicated than this, but not much. Until you understand how stock splits work and why the "inflation" created by stock splits is only an accounting adjustment and has no economic relevance, you will never understand Steem.
That is not correct. Steem sends some of the money it creates to others, not just the persons holding SP.
Bottom line is someone has to pay for the payouts to bloggers and curators. It isn't all proportion to stake.