Chrome solved this a decade ago... just keep shrinking the tabs down to Favicon size or smaller. Safari just added Favicon images last year, and I don't even think they're visible by default.
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EDIT: Favicon-only compact tabs to have actually been changed/added in Safari 14 for Big Sur!? Which would actually probably push me to switch (and upgrade to Big Sur, even).
> https://9to5mac.com/wp-content/uploads/sites/6/2020/07/macOS...