alt Hacker NewsWell, it's not like it's a simple black and white situation, universally applicable to every debate in human history. Sometimes it is relatively better to be open-minded and able to change own opinion. Sometimes it is relatively better to keep pushing a point if it is rational and/or morally correct.
The reason why the latter stance is often popularized and cheered is because it is often harder to do, especially in the adverse conditions, when not changing your opinion has a direct cost of money or time or sanity or in rare cases even freedom. Usually it involves small human group or individual against a faceless corporation, making it even harder. Of course we should respect people standing against corporation.
PS: this is not applicable if they are "clearly wrong" of course.
Consider the plight of a policy-maker who changes their stance on some issue. They may have changed their mind in light of new information, or evolved their position as a result of deeper reflection, personal experience, or maturation. Opponents will accuse them of "waffling" or "flip-flopping", indicating a lack of reliability or principles (if not straight-up bribery). Elected officials are responsible for expressing the will of the people they represent, so if they're elected largely by proponents of issue X, it is arguably a betrayal of sorts for them to be as dynamic as private citizens.
This is tangential to the original topic of insider trading, where the corruption is structural / systemic -- akin to how "conflict of interest" objectively describes a scenario, not an individual's behavior.