It is probably the worst when playing support, but ultimately it shouldn't really matter. No doubt match making is off more this season than in past seasons but ranking up is still possible.
I mained support earlier this season and got form silver 5 to gold5 fairly quickly. I got sick of playing support after that but I did learn a few things that has helped me adapt to other roles and find success in continuing to rank up. I noticed at certain point I started struggling more in lane. Obviously if you can snowball a lane and get your adc fed then you want to do that. If not then not feeding the enemy team is also important.
For me ranking up playing support was all about what I did in the mid and late game. A lot of my games started off my team beating the enemy or the enemy beating us. But I found a lot of times by the mid to late game, the games started to even out and I started to have a large impact on the games. From warding to my peeling or catches, any plays I made started to effect the game a lot. Since death timers get so long winning a team fight is key. So if I could pick off any enemy player for my team with a
or
snare while they were away from their team, it was a huge advantage for us. Or in team fights if I made sure the enemy team never got to my adc then we would end up winning the fights and usually winning the game.
I think a lot of players no doubt get frustrated and support can be a really frustrating role. But I noticed playing in low elo that a lot of games are thrown so as long as I stayed positive I could have a large impact on the mid and late game, which ended up in my team winning more games than losing and allowing me to rank up.
Now I just play jungle or adc as I find them more entertaining and feel I have a larger impact on the game and have had an increase in win percentages. There will be blow outs, but I have seen a lot of close games this season. I think the key is to not give up right away and staying positive even when the team is behind. If there are negative toxic players on team I just mute them as their chat only tilts me and makes me play worse.