Please help!

Hello knitting community. I've had an issue basically since the beginning of my knitting journey and I'll try my best to explain it. I'm hoping there's an answer to my issue.

I've been knitting since 2017 and I was gifted an old Boye interchangeable circular needle set (pictures 1&2)by the person who taught me. Not sure when or where she bought them. Even though they were well loved by her and showed wear and tear, I continued to use them and loved them! However I have always had a specific issue I have no idea how to fix. With my 40cm cable (picture 3 shows US size 7, 4in needles, and also pays the cat tax), I find that my needles are too long and I can't actually knit. Picture four shows the cable and needles in a relaxed position. But when I try to put the needles point-to-point to actually knit stitches (pictures 5&6), the cable stretches taught, whatever garment I'm knitting stretches out, and I still can't move stitches between my needles without completely stretching the stitches. Usually I avoid this cable and just use dpns for hats and small cuffs, but I've wanted to make more sweaters and this makes it impossible to do collars and sleeves. I know I could just opt for a longer cable and do a magic loop method, but then what's the point of the 40cm cable??

I've been toying with the idea of buying a new set of interchangeables, hoping this is just an issue with this older set, but I want to know everyone's opinions on this before investing. Is this a me issue, am I doing something wrong? Is this an issue with this set? ( If so, please leave recommendations for a new set, preferably metal!!) Or is this just the reality of the 40cm cable? Please help!