Why just 30 level? think about it

i understand that there's should be a limit ! BUT
after 30 level the only way to get "higher" is by playing ranked and get up to challenger (which is great..) but there are a lot of people like me who don't play ranked because we know it's a 100% TILT factor plus most of players won't turn into youtubers/streamers as we play for fun ...

Why the limit if just 30 level? why not 100? (or even more) and every 20 levels you get a border or a ribbon or something like this on your champion border on loading screen and profile .

we can keep that level 30 for ranked ... and then keep leveling up for more stuff like rewards etc ..

For example : i started playing overwatch some weeks ago , and i see that besides ranked borders there are level borders plus STARS which every 100 levels your level resets back to 1 and you get 1 star on your border . Wouldn't that be kinda interesting ? [slayer-jinx-catface]