That's entirely dependent on the industry. For many, IT is a support function. It can enable and enhance growth but not cause it on its own.
We also need to be careful when we use the term "IT". The popular press and casual conversation often lumps anything that has to do with electricty as "IT". I make a distinction between traditional IT services (voice, data, video, presence, storage, etc.) and more product-oriented engineering type work.
I think the confusion comes more from non-technical people who are completely oblivious to what IT does and how it can benefit the company, and therefore confuse consumer electronics and products for Business IT and Systems.
They are two completely different animals.
Dead giveaways of this mentality are people who stay stuff like:
"Geez, can't you just build an app for that?"
"My kid is a wiz with computers, you should see how quickly he installed Minecraft, it's amazing what he's done there."
"Can you take a look at (insert personal consumer electronic device)?"
...list...goes...on...
In my own personal experience, I have an in house POS/CRM system that I've developed. We work in retail insurance, mostly Personal Lines, but we have a growing Commercial Lines business. They (Sales and Operations) don't like my POS/CRM system for that. Why? Well, because I designed it around Personal Lines. So, it's built around their work flow, and I programmed it by literally sitting down with Agents a few days and doing their jobs with them.
Could my system be expanded to serve Commercial Lines better? Sure. But, I'll need to be educated more about what exactly they need. And, a short e-mail or a few sentences in a group meeting doesn't cut it.
So, instead, we are going with an off the shelf SaaS product that does nothing that we want exceptionally well, but does do things my system will not. They aren't happy about it, but refuse to put in the time to educate me (the programmer) as to what they really desire.
Many places see this as a failure of IT to support their needs (including my company, which is very dedicated to in house IT)...but, the fallacy comes when they begin to BLAME IT for this, and then come to one of two conclusions.
1) Why are we paying so much for IT when they don't do what we need?
2) We should just outsource it all?
And, the core of this, related to my original statement, is a sheer misunderstanding of the difference between consumer electronics/products and IT Systems (and I'll note a complete disregard to data integrity and security...there's a reason why major data breaches have increased as more has been shipped out).