I'm not alleging collusion, I don't believe there is any active collusion at all. These things are possible through just incentives. E.g. consider a hypothetical streaming providor; compute is cheaper by the year, cost of owning your datacenter goes down by the year, your customer base grows by the year, the amount of money you return on investments like productions continues to pay out by the year, yet your shareholders expect you to raise prices by the year as well despite productivity increasing, customer reach widening, and your costs lowering. Imagine a CEO arguing they don't need to raise prices like the board wants in order to see a bump in the speculative markets on their investments, they'd just sack that CEO for someone who will.
That's just for the hypothetical streaming agency. When you add up all these little increases of just about every good and compare that to wage growth, you see that wages are stagnating relative to other metrics like cost of living or business/national productivity, in the US or the UK or just about anywhere with these sort of metrics available. You can raise minimum wages to fend of a total economic collapse every now and then but these increases find their way to these other hands reaching into your pocket before long as well. A constant sucking noise and a march to what, I'm not sure, but it won't be pretty I expect.