after update 1.13, all (all types of zombies) infected melee range is vastly increased. I didn´t find anything about the change inside patch notes. Is it intended or not? Zombies can now attack you from distance of cca 2.5x their arm length, it doesn´t match with animation, you can´t intuitively avoid their attacks and it looks ridiculous.
Before patch you could literally run in circles (not sprinting) and zombies attacked ocassionaly, That was not good design, so you added more agile runners. But don´t increase overall melee range beyond animation range. If you want to go hardcore, learn zombies how to do sharper turns, how to climb on objects, make them even more agile, but dont give them invisible shovels!