That's how people see IT but not how it usually applies to the company in the big picture. They're are two types of big picture IT jobs, supporting the company network and selling or helping sell shit outside the company.

Within a company in which you are providing services to the company's infrastructure, there is no corporate ladder. There are only roles to fill and the needs are typically static. Manager, network engineer, Microsoft engineer and desktop support whatever. There is no promotion job title. Just salary. The company doesn't have a need for an IT ladder, the only growth is lateral to meet work load. Or replacement. (IMO bigger the company the smaller you matter, regardless of the position.)

Also keep in mind that IT departments usually have a fairly fixed budget. Want a raise? Find a way to save the company money or increase the productivity for the people directly making the company money since you aren't directly making them any.

The obvious flip side is selling or helping sell something. A product or skills as a service. Usually both at the same time.

I've worked on both sides of the fence. If you're providing a good infrastructure, you have excellent security and potentially a lot of fuck around time if everything is working, but minimal salary increases and no corporate ladder. If you're good at selling or helping sell shit, it's a lot of consistent work but the potential for job title and salary growth is much higher.

Now that's in regards to permanent positions. Contracts are just hired work. Some companies only staff enough to maintain and any new projects are contacted just to get them to the point of only needing to be maintained. Lots of money, no benefits, no security, no consistency.

IMO - Be good at what you do and do it with people you like. Different parts of the grass are greener on both sides. But NEVER EVER let a job, company, or manager make you feel worthless. Find a place the value is mutual and articulated, because job titles only matter on the outside.