He most certainly did hit the lottery. If you looked at Simpson before the draft and asked "what is the best possible situation he could land in through the draft among the 32 teams?" the Rams situation would stand head and shoulders above the rest. Not merely a solid starter he can learn behind with no pressure, but the reigning MVP and future HOFer. Not just a decent head coach, but possibly the best in the league and one of the most innovative minds around. Not just any offense, but an offense that is geared towards the things he does well.
Although I was initially taken aback by the pick, I can certainly understand the logic behind it, and when you put it in the context of the situation he ended up in, it makes perfect sense.
Also, as a rebuttal to some of the critics of the pick, if the Rams win it all next year (which they can with their current roster - a pick at 13 won't be the ultimate difference maker) and Stafford rides off into the sunset, many would have asked why didn't the Rams take advantage of the 13th pick and grab a QB when they could have. And I'm confident the Venn diagram between those critics who would later bash us for not preparing for Stafford's eventual retirement are the same ones who are the loudest about the Rams doing so now.