Some anime are so popular that even people who don't routinely watch romance anime recognize the titles or characters. Sometimes anime fans are aware of classic romance anime on their radar but starting a series with a big fan base can be intimidating. Sometimes anime are popular mostly for nostalgic reasons and may not hold up to newer audiences, but there are plenty that earned their popularity and will still hold up with new viewers.
Source：https://www.cbr.com/overrated-romance-anime-classics/
