Tents get wet and should not be inside dry bags.
Wet tent goes into a plastic grocery bag , and then into my rackpack. Never had a problem with "cross contamination". The most it stays in in the bag is for the day or two days at most before it is either used or dried out.
Don't forget that synthetic insulation, and to a lesser extent down as well can be injured by repeated compression cycles. If you use a compression sack for your sleeping bag, you will reduce it's ability to loft, and subsequently it's warmth over time.
That imay be true, if you stored your bag compressed all the time. I've used compression bags on my synthetic and down sleeping bags for years, While I can't scientifically prove that they did not lose any loft, empirically they are just fine. They are removed from the compression sack almost every day when in use. I have been on 3 month tours when my bag and tent have been carried in compression sacks. They are NOT stored that way when not in use. It is probably harder on the tent than the sleeping bag. However my tents have also been carried compressed a lot without any apparent damage. A couple of our tents are 10-15 years old with a lot of hard use, and are still fully functional.
This is the size of my tent and rainfly in a compression sack. The sleeping bag goes into the same type of compression sack, only smaller. It is made out of waterproof sil-nylon and when a wet tent is place inside of it and then placed inside of a plastic grocery bag, it rides well inside a dry bag without getting anything else wet. BTW- mold has never been a problem, even in damp humid areas.
