Whether students having access to old exams or not is cheating, depends on a few things. If the instructor knows that it is common then s/he will probably act with that knowledge and not overly use old exam questions. In such a case, it would even be valuable for the professor to make an exam bank available to everyone. See this recent question for more perspective on this particular part of the issue here.
But there is more involved.
Every situation is different. When I was a student it was common for fraternities in the US to collect old exam questions. None of the three top math students at the college I attended were members and so didn't have access to these, nor other similar resources. But we all did (better than) fine and all ended up with PhDs. While the exam banks may have helped a few avoid failure, it had no real effect on things when looked at from a wider perspective.
Also at that time it was believed (possibly apocryphal) that at a certain very top graduate school in the US, no student would consider taking a course for credit unless they had already audited it once. I don't know if that was true, but it points to the pressure to succeed that students often face.
Next, I believe that no course that you ever take will ever be able to tell you everything about that subject. It will only be a surface skim that covers the important points and techniques that enable you to go further. Moreover, it represents, even in traditional subjects, only a snapshot in time of the thinking in that field. History moves on. Mathematics moves on. Hopefully a course will give you the tools to move on with your chosen field. But it is unlikely to be a lot more than that.
For the above reason, I have saved nearly all of my notebooks from courses I then considered important. I wrote on paper (not very good paper, actually/sadly) and took care of them, so I still have access to notes from math courses I took more than 50 years ago. I have a copy of a paper I wrote in secondary school (around 1960) and consulted it recently for another project. I have a deeper understanding of all that now than I did then.
The reason for saying the above is to comment on your professor's giving you such a "load" of supplementary material. You should ask about it, but I suggest that s/he is helping you build an archive that will be useful to you over your professional career, not just resources to pass that particular course. I once took a writing course from one of my "great" professors. He would seldom talk about writing (though he made us do a lot of it), but would spend lecture time recommending books to read. In a week, he would recommend 30 or more books. Who could keep up with that? And no, we didn't need to read them to pass. We needed to write and write and write.
Finally, though I may supplement this after some reflection, every student is different. You may or may not need to have access to a gigantic exam file, but I doubt that you will provided that (a) you are serious about your subject and (b) you practice with the knowledge you are gaining by doing exercises and getting feedback. Doing more than the minimum number of exercises, in fact.
That said, it is useful, and the prof should support it, if you are able to see one or two old exams, just so that you have an idea of the kind of question that the professor uses, if not any actual upcoming questions. In some places that would be against the stated rules, unfortunately.