And yes the respawn timer changes for the winning and losing teams. The difference also depends on how far behind the losing team is.
you are over estimating the consequences of that system. it will help the losing team get back on track, sure, but if they manage to actually take the lead, then the same system will now help you to comeback and secure the win.
if you are leading by 400 points, and you lose, don't blame the system... it used to be borderline dumb before this patch, now it works just fine. the respawn timer range isnt that wide anymore.
also, without these rules, the team with more early-mid game champions would have an unfair advantage.