Masquerading as Chrome is a mildly inconsiderate choice for an RSS reader to make, especially in not including a token for their own site. User Agent strings for visiting websites are a mess because of a history of people coding only to the dominant browser, but RSS does not have that history.
You do see things like Feedly using Feedly/1.0 (+http://www.feedly.com/fetcher.html; 452 subscribers; like FeedFetcher-Google), where they include the FeedFetcher-Google token, but there's really no reason to pretend to be a browser.
Looks like QuiteRSS has pretended to be a browser for years: https://github.com/QuiteRSS/quiterss/commit/38ad3ce6e72f90036f1db14568f33dbf346fc1b3 Opera/9.80 (Windows NT 6.1; U; YB/3.5.1; ru) Presto/2.10.229 Version/11.62
I use QuietRSS which sets its User-Agent to "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/77.0.3865.120 Safari/537.36"
Source: https://github.com/QuiteRSS/quiterss/blob/271c55756dcf19ca163a603a54d12f165548a602/src/main/globals.cpp#L98