Is time-wasting a tactical skill or a problem to fix?

Every team does it at some point, and referees handle it inconsistently.

Should time-wasting be treated as game management, or does the game need stricter rules?

It definitely falls under game management right now, but the inconsistency from refs is what drives you mad when you're trying to salvage an acca late in the game. You see one team get away with taking an age over every goal kick from the 60th minute, and then another gets booked instantly for the exact same thing. If they want to fix it without ruining the flow, stop messing around with added time calculations and just put a strict countdown clock on restarts like they do in other sports. Do you think a clock stoppage would actually stop managers from instructing players to slow it down, or would they just find another way to disrupt the rhythm?