I’m posting this link because some of the points mentioned in here remind me of Asian clients I’ve worked with who’ve had trouble speaking up in meetings. Some of that resistance is cultural – a desire to be respectful to the more senior members of the team, but unfortunately, in the American context, it can be interpreted as not contributing enough or being needlessly passive. This article doesn’t address cross-cultural behavior but has some good tips nonetheless!
https://www.fastcompany.com/3052599/the-top-3-reasons-introverts-dont-speak-up-in-meetings