I can only speak for myself, but that's incorrect. It's also incorrect, anecdotally, for some of the chaps i've started playing AoS with from around my area.
I came back to GW after almost a decade away. When I came back, I was basically a total new player, I hardly remembered any of the rules and, in the case of AoS, had zero knowledge on how it worked. I only decided to come back after reading the rules online and browsing through all of the freely available warscrolls. Sure, I had little context to what they meant, but I at least felt more prepared to start playing a game none of my friends played.
Free rules from an established company indicate one of two things:
1. The rules are secondary to the models. They're their to drive model sales and aren't meant to be a main focus, just something for you to do with said models. Which is actually a good model.
2. The rules are free to facilitate a competitive environment, as free information is the bedrock of any competitive scene. The company is selling you a system, rather than just models. Warmachine & Hordes typifies this.
AoS falls (fell?) squarely into #1. It's why I decided to buy-in, because it was a goofy ruleset with ostentatious, ridiculous models. It felt like it would feel good to play all the way from the models to the rules. And it is! So I bought both the battletome and the rulebook when I picked up the models I need. But free rules are a signpost to how a company views both its customers and the ecosystem for its models. Not free rules, in this day and age, are like getting a faint whiff of mold when you enter a hotel room. Not necessarily a deal-breaker, but not a great sign either.