This is 100% consistent with my experience. Its been clear that they are nerfing it on the back-end to deal with copyrighted material, illegal shit, etc (which I also think is bullshit but I accept is debatable).

Beyond that however, I think they are also down scoping the queries from 4 to 3.5 or other variants of '4'. I think this is a cost savings measure. Its absolutely clear however, that 4 is not what 4 was. The biggest issue I have with this is the issue of "What am I buying with a call to a given OpenAI product?". What exactly am I buying if they are re-arranging the deck chairs under the hood?

I did some tests basically asking GPT4 to do some extremely complicated coding and analytics tasks. Early days it performed excellently. These days its a struggle to get it to do basic asks. The issue is that not that I cant get it to the solution, the issue is that it costs me more time and calls to do so.

I think we're all still holding our breath for the 'upgrade', but I don't think its going to come from OpenAI. I need a product that I'll get consistent performance from that isn't going to change on me.

Could it be that so many is using it that they don’t have the capacity anymore? This technology does require crazy amount of resources to work.

You are not wrong: https://arstechnica.com/information-technology/2023/07/is-chatgpt-getting-worse-over-time-study-claims-yes-but-others-arent-sure/ and also https://duckduckgo.com/?q=chat+gpt+4+getting+worse

The more LLMs get exposed to data, the more they get exposed to wrong data. There's also a vicious cycle problem that once LLMs spit out bad information, that bad information gets incorporated into LLMs new data sets, which makes them more wrong, so on and so forth.

There was just a post on HN about how GPT-4o is best at long context. Try that.