When I place one million blocks at once my computer freezes for a while, which isn't a problem, since I can do something else in the meantime. On a server, however, that's not so good, which is why server owners keep the maximum build area pretty small. While you can place large numbers of the same block type bit by bit, using templates, that are bigger than the max build area simply isn't possible.
If we had a server setting to limit the number of blocks or chunks placed per second, server owners could make the max build area bigger without fear of server crashes. Whenever a player tried to place more blocks than allowed, excess blocks would be queued and placed piecemeal.
If we had a server setting to limit the number of blocks or chunks placed per second, server owners could make the max build area bigger without fear of server crashes. Whenever a player tried to place more blocks than allowed, excess blocks would be queued and placed piecemeal.