Wholeheartedly agree. It's sad to slowly see the bitrot in my own bookmarks, trying to pull up important resources or media from only a few years ago only to hit a 404 or domain placeholder. And many times there is nothing on Archive.org or similar.
That ArchiveWeb extension looks excellent for custom captures. Picking the pages and elements you want during capture is a great feature.
For quicker one-offs, SingleFile gives you a single HTML with all the media of a page: https://www.getsinglefile.com
If you're making archiving a more involved part of your workflow, I highly recommend ArchiveBox. It can save pretty much every type of file from everywhere, in almost every format you can imagine, while building a searchable index of the archives. Been using it successfully for many years: https://archivebox.io
That ArchiveWeb extension looks excellent for custom captures. Picking the pages and elements you want during capture is a great feature.
For quicker one-offs, SingleFile gives you a single HTML with all the media of a page: https://www.getsinglefile.com
If you're making archiving a more involved part of your workflow, I highly recommend ArchiveBox. It can save pretty much every type of file from everywhere, in almost every format you can imagine, while building a searchable index of the archives. Been using it successfully for many years: https://archivebox.io