Absolutely ridiculous difficulty curve going from Draft to Ranked for the first time (?)

I started playing League in February and have been playing hours a day, every day. I'm not the most flexible when it comes to champion selection yet, but I started with and ended up maining support (I got my mastery 7 with Nami a month in and usually get at least one S+ per-day with her now, most games being victories), and I end up winning my lane pretty much 80% of the time in Draft. I got into jungle as a secondary role, maining Jax and Evelynn, and I've been doing consistently well enough lately there too, to the point where I thought I'd finally give these roles in ranked a try.

(I have played a bit in every role, so I'm not ignorant towards their struggles.)

I've done four solo/duo placement matches now and have gotten absolutely destroyed, losing all of them. Three of them were with Nami support (since it's what I'm the most consistently good with), and every time we lost our lane before the ten minute mark. It wasn't just me though, all of our lanes got pummelled.

To go one step further, everyone in all of these games were absolutely obnoxious and I got flamed to no end for things I felt were out of my control (they probably weren't, but I felt they were in the moment). I'm an incredibly tolerant person, so to me, flaming your teammates who are genuinely trying is the pretty lame. I know this attitude constitutes 50% of the playerbase, but it's really hard to tell when 100% of your teammates in all four games were doing this, including the classic post-game outcry in an attempt to get approval from the enemy team ("I just wish I had a support who knew what they were doing"/"noob bot lane"/"**** useless support"/"back to bots") to which I'd finally reply "that's a lot of anger", and get "fk off Nami" in return.

I mean, yeah, whatever. I'm not the sole target of the flaming (though I have had an absolutely nasty ADC every single game who manages to rile everyone onto their side), so it's not like I'm the sole reason every game was lost. I obviously had a key role in it, as do the other nine players in each game, but I'm trying my best.

In the one Jax jungle game I played, I did about equally as bad, but again, it was one of those scenarios where every one of our lanes was getting destroyed and I didn't really know what to do, and then got yelled at by the ADC for not specifically thinking to jump over the raptors wall to take out a lower-health Jhin who was near two other fed teammates of his. Their Warwick absolutely dominated the game and I didn't stand a chance early on, aside from one lucky kill I got on him while I found him trying to steal my Blue.

I wasn't expecting to land above Silver V or something given that I've only been playing for a couple months - and honestly, I think I'm doing very well given how not-long I've been playing - but I don't really know what to do here if I'm going from doing so consistently well in Draft to being completely, almost 100% useless in solo/duo ranked. Is this a difficulty curve everyone can expect? Are placements more of a wildcard with who you're matched up with given that they're placements? Is this normally how people act in ranked, or have I just wound up with unusually obnoxious teammates in all four of these matches?

I'm not demotivated from playing at all, but I'm really wary about trying even one more placement match because I have to be doing something horribly wrong - at the same time, I know that, while I was probably consistently one of the worst players on our team each game, even if I wasn't, we probably wouldn't have stood a chance. I'm just not really sure what to do, since at this point I'm expecting to end up losing all ten of my placements and wind up with the rudest teammates on all of them. I'm aware of /mute all, but I don't want to hinder any important communication.

[sg-jinx]