Is it true that instantview works to some extent like a cache of pages on telegram servers?

Question

Telegram

Created a template for instantview for a specific page of my site. But when I throw this link to someone, or for example, when my bot sends a message with this link, the instantview button is not always shown and not on all platforms.
Do I understand correctly that instantview works to some extent as a cache of pages on telegram servers and there is no guarantee that instantview will be available for my particular page for all telegram users even if I went to the site https://instantview.telegram.org/ and specifically created a template for your links?