Ask HN: What is the least sycophantic frontier LLM?

My daily driver is Gemini, and 3.5 Flash seems more sycophantic and malleable than Gemini Pro 3.1, which is a pretty big deal for me -- I really need as much objectivity and impartiality from the LLM as I can get. So I'm contemplating switching to Claude or ChatGPT, and I wanted to ask about your experiences -- does any frontier model really stand out here?