Yea I wonder that too. At times the character worked rather well, but overall, IMO, it stands out as weird.
But, like you, I wonder if a Sinatra homage was just a much more natural and emotionally impactful thing for the mature fans (ie Boomers) watching in the 90s. I’d bet that it was at least less weird. Like at most they thought, “huh, writers are Sinatra fans … ok” … ?