I would recommend more iconic sights like Christ the Redeemer and Sugarloaf to folks visiting the city for only a day or two, but if you’re staying longer and seeking additional things to do and see, I suggest you spend an hour or two at this museum, especially if there are free admission days and the weather is good enough to tour the outside. Like others have mentioned, I do wish there was more, and I feel the entry fee could be lowered for the quantity of offerings, but this doesn’t mean you should avoid the museum entirely.
A nice cafe is inside with a good selection of items (at high prices for the portion sizes, though), and the staff are all friendly. Wheelchair users can navigate the facility with ease, and exhibits are translated for speakers of English and Spanish, as well as Portuguese of course. Some smaller displays out in the halls on the second floor lacked signage in any language, which made me confused as to what I was looking at, but most areas were equipped with either physical labels or technology that enables visitors’ phones to capture the info and show it to them or activate sounds.
Once done with the inside, I strongly encourage everyone to take a bit to stroll the museum grounds by the water and near Olympic Boulevard. The vistas are wonderful, and in good weather like during my visit, it’s an awesome place to eat food and/or people-watch. The way they constructed the museum allows for the best in-and-out combo of seeing the exhibits and enjoying fresh air around a stunning piece of architecture that is the Museum of Tomorrow.
Thanks for a nice visit!