Earlier quoted context omitted.
For me, chat history has a huge value. How many times things looks like meaningless when they are said but have a lot of values at a later date? For example, sometimes you wonder, "when was it that time when XXX event happened". Or "I remember that one day someone told me that he had the same problem as me, but who was it and what was his solution?" Otherwise, we are used to share thousands of links and snippets with…
Sure, but wouldn't you want to have control over these backups yourself? Not only do you get increased privacy from it, you also won't be in for a nasty surprise when the service decides to remove old logs/stop doing business.
But sure, the best thing to deal with that is to be able to 'backup/export' your history and also being able open/import it in a usable form.
Whatsapp mostly fails on both topics. You can't easily backup, otherwise it would be stored in clear in google drive, in an area that is not even accessible to you.
And then it is a sqlite db with proprietary format for fields, so so far nothing can display it properly offline.
For telegram, they have a good export/backup feature.
I don't know of anytool that would allow to browse your history nicely when loaded offline from backups, but as the format is open, that should be doable.