My wildly-speculative guess: some executive saw someone use “Inspect Element” and hosted an urgent meeting about how to solve this security risk. Rather than try to explain why it’s not a security risk, the dev team just placated the exec by saying “we could just disable right-click.”
Actually, I've seen many videos of Indian scammers using "inspect element" to generate some fake "accidental money transfers" on their victim's bank account. They'll invent some way to make their victims believe that they've done something wrong and that they've received too much of a "refund" and then they'll either go the "I'm going to lose my job please send back the 30,000" card or the "this is a crime, the fbi will call you if you don't cooperate" card.
Making it difficult to inspect element+replace value might actually be worth the effort. I've seen a Kitboga video where a simple transparent div covering the entire page had the scammed stumped for minutes because they didn't actually understand HTML.
It certainly doesn't prevent viruses, but for scams it may just be enough to save some people.
To inspect element one can just open the developer tools from the menu or the shortcut key, and then use the "inspect" tool from there, this bypasses the context menu block.
I suppose low level hindrances are sufficient to block low-level intruders...
This might actually accidentally be an argument for this approach, because the amateur scammers get frustrated at the very least but actual developers are capable of doing whatever they want.
It's a tricky trade-off. I don't think it's worth the effort and inconvenience to block the right click menu, but in the fight against scammers I can see why someone would see otherwise.
In the old days (CompuServ and AOL era of the internet) a lot of sites used it as an easy way of reducing the number of 'right click, save picture' type visitors. It never stopped the determined but reduced it by at least 90%. I have no idea why it is used today though.
I just saw someone request that the creator of a photo sharing site disable right-clicks for the same reason last month on reddit. I think I talked them out of it.
Probably some combination of security theater and well-intentioned but shallow, nearsighted and misguided attempt to increase security by reducing a perceived attackable surface area (i.e. likely somebody got scared with "View source" or something like that).
A lot of Japanese lyric websites disable right click. My hypothesis is because the Japanese Collection Society have very backward thinking about sharing lyric.
