Judging by the comments here, there seems to be some confusion.
This is exactly like long-lived cache settings today. Right now browsers send a request on basic reloads and get back a 304 from the server which states that nothing has changed. All this setting does is let the server tell the browser to skip that check/roundtrip instead of wasting the time/bandwidth on confirming with a 304 after the initial load.
The browser is still completely in control here and can do a full reload or just reload all the time if it wants to. Web scrapers and other HTTP clients are unaffected.
This is exactly like long-lived cache settings today. Right now browsers send a request on basic reloads and get back a 304 from the server which states that nothing has changed. All this setting does is let the server tell the browser to skip that check/roundtrip instead of wasting the time/bandwidth on confirming with a 304 after the initial load.
The browser is still completely in control here and can do a full reload or just reload all the time if it wants to. Web scrapers and other HTTP clients are unaffected.