The lifters are spring loaded, so they are easy to depress to some degree. However, there should be ample resistance. If you can bottom out the lifter with your finger or depress it easily, then you may have a problem.
The lifters will pump up when started, but it's easier to prevent a problem now than fix one later. For about $8 a lifter, I'd go ahead and replace the 2 culprits now.
HTHs
Hood