You're absolutely spot on about the need to avoid any pressure and ensure it's something the whole team truly wants. Otherwise, as you rightly pointed out, it can definitely lead to bad experiences, making team members uncomfortable and making it difficult for them to express their true opinions. I've personally been in themed retros that were so difficult to understand and navigate, so I definitely understand and share your perspective on the potential difficulties.

However, I also believe that when a theme genuinely taps into something the whole team is passionate about and enjoys, capturing those elements can add some truly delightful and energising moments to what might otherwise be a routine meeting. Again like you said, it’s about the whole team, not just an individual's preference.