Polls are not a Mastodon-specific feature, they can be expressed well in standard ActivityPub, which means standards-based apps like BrowserPub can render them
Here is a recent poll example from @evan
https://browser.pub/https://cosocial.ca/@evan/113005485605693174
looks like someone submitted it to hacker news!
https://news.ycombinator.com/item?id=41351408