@Alphabets
Definitely leaving has an impact on the game of some players. But I have seen people solo to victory often enough to know that it is possible.
What if someone has a bad connection? Devs spoke about trying to not penalize players with a bad connection, when talking about lag compensation. So I would guess that Devs would not really push for a leaver penalty in pubs, when players are allowed to join games with a latency of 250ms, feel the game performing poorly and consequently wish to leave a match and look for another one which with a little luck may be on a closer server? Not all areas are serviced equally.
https://www.ea.com/games/apex-legends/news/servers-netcode-developer-deep-dive
See the part on lag compensation.
Also, sure that is the mentality --but Apex is only a casual game. Devs develop it around the casual player. Sure there are competitive aspects, but are not really supported as they are in other games made to be competitive,see for example Valorant.
Perhaps matchmaking needs be done better too? But this, again, would imply that devs want to attract a limited audience made of players who can afford to take the game more seriously.
Yeah in a potential Ranked mode Arena, something to stop leavers would be appropriate.