This is my thinking as well. Although the 'never do full rewrites' rule is canon for most of the software world, I have led rewrites of two large front-end applications to great success - replacing an app that 'worked' but took an order of magnitude more time to iterate on than the codebase that replaced it.
That said, it's probably more dependent on what a 'full' rewrite actually is - I would be much more reluctant for a full-stack rewrite, particularly of a mature codebase with a lot of accumulated business logic. At least on the front end you can always push to move business logic upstream where it belongs.
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I do feel like rewriting a front end that depends on the same backend is much less perilous than the alternative - in the end its basically just a presentation layer change