You're not suggesting these particular songs are clones of each other, are you?
Same shmalzty lyrics, same basic 4/4, same intended audience of pubescent girls with their first crush. These songs are the "pinacle" (if it ever had such a thing) of the 100% generic cheesy love song. Every stupid whiny uninteresting love song since, all the way up through the latest from whoever won American Idol this year, traces it roots right back to these songs. Pure song factory mimeography.