It may also be that webflow rate limits bot traffic? Try spoofing the user agent with a popular browser's[1].
But why scrape? Webflow allows to export the code[2]. But it may still require premium subscription, I haven't looked thoroughly.
[1] https://techblog.willshouse.com/2012/01/03/most-common-user-...
[2] https://university.webflow.com/lesson/code-export