No and no.
There is no time when the pressure is greater on the seals than when you are riding.
If you compress your forks 50%, you are barley compressing the air inside anyway, so the 'pressure' argument is wrong.
If your seals leak, they are probably dirty, or the wiper is dirty, holding in dirt under the seals.
Adding pressure for a long period of time allows the slow leak to show itself.
2. The compression of the air space is gradual. Reducing the air space will be felt by the rider from the middle of the fork's stroke to the point of bottoming. The corollary is that when you take oil out of your forks, you make them softer from the midstroke on. It has little effect on the first four inches of travel. If the pressure argument were valid, oil would squirt out of your leaky seals the moment you compressed your forks.