In theory you can do pretty much any job in "IT" up to and including CEO of one of the biggest companies in the world without a degree - it isn't like it is a regulated field. In reality you might find it much tougher to land a particular role in some areas without a degree and/or to even get the required background for some roles - that isn't to say it is impossible but in some cases if you've studied the material anyway then it would seem a bit silly not to also get some recognition for it. For some roles you'd need to have self studied significant amounts of material anyway so it why handicap yourself by not just getting a degree for it too?
I think if you're doing something beyond general IT/vendor certificate type roles then a degree is a bit of a no brainer if not a masters too (depending how much you want to specialise) - it just increases your chances in many areas/opens potential doors etc..etc..
I know business analysts, developers and product owners without degrees but those roles, in some cases, can be somewhat basic or at least not require particularly deep levels of knowledge.
If you want to work on self driving cars or in data science or if you're fancy working on the latest GPUs at Nvidia or in a quant role at a bank or as a machine learning engineer at some start up then you'd best have an undergrad degree in the vast majority of cases and often a masters or PhD too. Often not necessarily computer science at undergrad either but mathematics, physics, EE etc..
