On this topic, now that GPT-4 without Bing is available on ChatGPT Plus, it’s noticeable that Bing slows down the generation and can make the output much worse by including Bing crap in the context.
But it’s also sometimes better at things the normal GPT doesn’t know about. I think it’s going to be the best search engine once they improve the speed.
Bing has to be slower since it mixes in context from the web. So technically it does a Web search, feeds the results into ChatGPT, while ChatGPT itself doesn't have this step.