According to this thread: https://www.thefirearmsforum.com/threads/red-and-black-ruger-logos-whats-the-difference.126490/
The logo changed color when Sturm died as a sign of mourning and changed back for their 50th anniversary.
The text updated with the release of some newer firearms, likely as a marketing strategy to show a modernization move. They probably use both as a way to show deference to their origins with specific firearms and then the newer text with the more recent lineup. At least that's my best guess based on several minutes of googling lol.
The logo changed color when Sturm died as a sign of mourning and changed back for their 50th anniversary.
The text updated with the release of some newer firearms, likely as a marketing strategy to show a modernization move. They probably use both as a way to show deference to their origins with specific firearms and then the newer text with the more recent lineup. At least that's my best guess based on several minutes of googling lol.