I've used the chat export feature of Telegram before deleting my WhatsApp account. It works well and convinced me to use Telegram over Signal in cases where I had contacts on both platforms.
(Personally, I'm also bitter that Signal Android supports backup while Signal iOS doesn't...and transferring from one iOS device to another isn't considered backup).
(Personally, I'm also bitter that Signal Android supports backup while Signal iOS doesn't...and transferring from one iOS device to another isn't considered backup).