I think this would be useful for people who have got Epaper/Eink displays. These displays have got low refresh rate and apps with animations usually would have bad UX on these displays.
Android already has an option to disable animations. If Delta Chat for Android does not respect it in some place, this is a bug, you can file a GitHub issue.
Thank you @link2xt and @Hocuri . It turns out BOOX OS which is a skin for Android, already has disabled animations. As for Desktop, I don’t think having proper support for epaper monitors has high or even medium priority right now. e-paper tablets are kinda widespread. But e-paper monitors are not. Lack of colour, the price and the usability all make the users avoid buying an e-paper monitor.
However, having an option to disable animations in Desktop could enable users of weak PCs(old x86 or new ARM) to have better performance.