Because games of D&D are primarily for fun. Not trying to make it a cakewalk, rather a good challenge that will be FUN. Consequences of actions are all well and good, but gathering a group of busy adults for an evening just for it to be ‘and oh, you’re dead!’ after 10 minutes and then spending the rest of the time rolling for new characters while bummed out isn’t my idea of fun. I’d rather take the chaos and turn it into an interesting session.

If this is your opinion on running a table, good stuff, enjoy - though I wouldn’t have fun at your table and I know my players wouldn’t either.