This is not necessarily true.

If the compressed length is short enough, this won't happen.

For example, on the 2000 - 2004 X's the shocks for the 3" SL fit the stock X just fine.

UNLESS the kit says you need a spacer or bumpstop extension, etc, to LIMIT the up travel...the shocks for a lifted truck HAVE TO be able to get short enough to fully compress, as the suspension of a lifted truck compresses to the SAME POINT as a non-lifted truck.

I tend to play it safe and MEASURE my upper/lower shock mount distances for both fully stuffed and fully drooped, to see what the shock must be able to allow. I typically add a buffer of added compression to account for stop squish, etc, and for over extension with leaf oscillation, etc.

For the X's, thus far, the lift kit shocks HAVE fit the non-lifted X's.

Of course, if you don't WANT the added wheel travel...its a moot point.