The dodging / protection system
I've seen this happening quite a lot, and honestly, I have also done this a few times. Someone gets filled in as support (usually how it is), everything is fine, game is loading, but the support is still at 0%... game starts, remake, the leaving player has protected status for his next game, and people that got their picks for the previous game, suddenly get to fill. fun times. plenty of times this has happened to me rolling mid/top picks, someone dodge, I fill support. And guess what I'm about to do to counter this? yup, same, dodge on load screen, have protected status, time lost? 5 minutes. Great system in place indeed....
I might be a minority here but I would rather que for 5-10mins, then be designed to fill support, for me thats a waste of 30ish minutes rather than a wait time for 5-10 minutes.
Now, there are punishments in place, such as leaving will give you a penalty wait time, this is only true if it happens often enough and consecutively, which it wont as you will have a couple games of protected and then a few where you probably won't fill, I average about 5-7 games before I get a support fill role so I have no danger of getting the wait timer.
There is a ranked penalty... not really, you have a higher chance of losing in a fill role you absolutely hate playing due to 1) mental state, and 2) lack of experience in said role, especially something like support, if you suck at it, your adc isn't gonna have a good time and their adc will be a hyper carry due to you being bad at support. the ranked penalty is what, 3LP? losing is around 17-20LP + 30mins of wasted time. to me, dodging looks more like a win than a loss in both scenarios.
Solution... I don't know tbh, maybe make support a more fun role to play, have items better suited for support? I strongly believe giving penalties and punishing players is not the right way to go, there will always be loop holes to exploit, having players forced to fill because the punishment is too severe will likely result in 4 other players not having a good time due to the filler having a bad attitude and lack of ability to play. A change in the meta is unlikely, but support specific items would probably make it a bit more interesting for some to play support and have more viable options for support, such as top mains that get filled can still use their main as support, albeit it wouldnt be the same but it might be less of a hindrance for them. either way, I do not have a solution, but There is definitely a problem with the current fill/protected system