I agree, It is just a normal day for me, heading to work later, etc, main difference is the TV schedule will be end to end Donald Trump in auguration, then more repeat showings and 'expert' analysis of the situation. Repeat for most of Tuesday in case people missed their opportunity to hear him talk.
Thankfully I am not on mainstream social media, the TV has an off button and I have more productive things to do.
As with a lot of things the term 'blue Monday' is there to get people depressed as they are made in a subliminal way to think it is depressing, it is an opportunity to promote therapy or 'expert advice' ultimately make money from people.