The reason one of the best practices for archival is completely reversible is since the frame components get contaminated over time you can eventually swap them all out with fresh components.
If you are going to forgo reversibility, you have two things to consider. One is will the process damage the print. Dry mounting can damage some types of artwork and some adhesives are harmful. Assuming the process is not harmful the next question is how permanent is the process. Permanence of the process is critical for longevity if you cannot reverse it and redo it later. Permanence is where dry mounting does very well and it is where spray adhesives tend to do poorly.