Many years ago, it wouldn't have been thinkable to use passive x\o's with large systems because of the low power handling capacity of the components in the x/o. Today it is different and in simple two or three way systems passive x\o's can be used to good effect. You have only to listen to some high end Hi Fi to hear how pure passive x\o's can be. However, there isn't the versatility you get with an active system which includes a modern day speaker management system. Not only can you tailor your x/o, you can time align the system.
It is true that a passive will offer some protection for the Compression driver, because it will only let a certain percentage of the power through, but with an active x\o you can choose you slopes and set limiters for protection.
Although some might think it unnecessary to use active x\o's in some situations, technically there isn't one reason why an active system cant be used in any situation.
When deciding which way to go, just try to think how the big boys do it, and although some of that equipment might be out of the price range, these days, there are good cheaper alternatives on the market, and it's this side of the market that improves all the time.
Whatever speaker components you buy, there will always be a manufacturers spec sheet. So that is your starting point, and the beauty of the LMS is that it is infinitely variable. So the world is your Lobster.