Recap: Reddit users have discovered what could either be a weird Easter Egg or a strange glitch in the Google mobile app on Android. It appears that when a user types "the1975..com" (without the quotes), the search results contain their recent text messages.
Owners of handsets from OnePlus, Samsung, LG, Motorola, and Huawei have reported that the bug/Easter Egg is present on their phones---I was able to replicate it on my Note 8 and V30---so it seems to affect all Android devices with the latest version of the Google app installed.
What's also weird is that the text messages appear when users type "zela viagens", "izela viagens" and "vizel viagens", as well as a variety of other characters such as "the1975.#com".
This function has been available on the Google app for some time. Users can bring up their texts by typing "show text messages," or some variation of those words. It also works via voice commands using the Google Assistant.
The texts will only appear if you've given the Google app permission to access your SMS messages. Access can be disabled, but that stops the Assistant from being able to read your texts when asked.
Typing "the1975..com" into the Google Assistant app on the iPhone has the same effect, though it "can't read text messages yet."
Quite why this is happening is still unknown. It's been speculated that it might be the work of one coder who's a fan of English rock band The 1975, who are releasing a new album on June 1. But it doesn't explain why it works with the other words.