The Issue with Current Dead Hard
First off I like the new concept of deadhard, requiring a precise activation rather than a free loop extender it used to be. Street Fighter 3's parry system is a favorite of mine so who wouldn't like reenacting evo moment 37 in dbd? However the issue with it currently is due to the very precise window of .5 seconds you often get screwed over because of lag/latency.
Based on your screen you might've pressed it at the perfect time to tank a hit but because the killer has 100+ ping you go down anyway.
This makes deadhard feel less of a skillful activation and more of a dice roll. You can't really react to a killer swinging as if they have slightly above average ping its too late. You have to guess when they are going to swing and hope you got it correctly.
If anyone remembers when dedicated servers first released and the "exhausted on the ground" memes were running wild its basically that all over again.
Not advocating for this perk to be buffed as almost nobody would agree to that but rather pointing out the limitations of an online environment really hinder this perk from being as "skillfull" or interactive as it could or should be.