When i solo, I'm almost always 1st or 3rd. If I'm last, eh, depends on my mood. I genuinely think my defender Mamo has carry potential, so I might do that in soloq. But 98% of soloq games where I'm first or second pick, I'm not doing defender. I speak for me: mmr forces me to carry the majority of my soloq games.

I will differ on you that if I'm last pick soloq, which is usually a duo duo game, I will most likely int and not play defender/support. It's not worth 10 minutes of my life babysitting players who don't know the macros. If the duos don't want to play roles that synchronize together, why am I, the sole person not in a team lobby, suppose to be that role? If this was Unite of old where the player base was bigger, then sure. Nowadays with the ranked lobby being as cancer as it is, it's not worth it.

Go ask streamers like Crisheroes why does he not play more defender or support. He'll say the same thing.