I'm not sure if this was mentioned or not, but I think for the most part it's an intentional humorous dig at Time Magazine, which as we all know is a bastion of leftist journalism.
If the picture parody was real, it would gall Time Magazine to no end to basically have to put the pic with the MAGA message on their cover, and acknowledge that Trump is doing a great job.
Then again, with a leftist piece of trash like Time Magazine, perhaps they wouldn't use the pic on their cover. They might fold their Democratic Party mouthpiece before admitting that Trump is doing a great job.