In Spanish we have a saying, "lo barato sale caro" which roughly translates to cheap things can end up being expensive. And that's what this experience was like. In all fairness, based on the previous reviews, it seems we had a one-off bad experience.
TLDR: The apartment wasn't cleaned and wifi didn't work at all throughout the 6 days we were there.
We arrived after 9pm on a Friday night and the apartment had not been cleaned from the previous renters. We tried to connect to the wifi to reach out to the hosts but the wifi network did not work at all. We then went downstairs to talk to the security at the front desk (he was SUPER helpful) and asked him if he could reach out to the host. After waiting a bit, he was able to get hold of someone but it was clear that we were not staying there that night.
Eventually, the host reached out and apologized for the house cleaner's "mishap." Didn't offer help or a sensible solution. All the while we're scrambling to find another place to stay for the night, that was within our budget. Needless to say, we found a place to stay but it was pricey and a total hassle. We had to change and cancel some of our plans that were scheduled for the next day because we weren't sure where we were staying. The communication with the host during this time was lackluster, delayed and it was late Friday night so we were just exhausted.
The next day we finally got confirmation that the apartment was ready (after 2pm) so we went back and tried again. Indeed it was clean. We tried to connect to the wifi and it still did not work. I reached out to the host and I received a picture of the back of the modem with the network and PW. We had already tried that, it didn't work. I had some work to do so this was concerning.
I reached out again and got no answer until mid-stay (4 days later). Said it was a building-wide issue. By this time I had already solved my own problem by buying a SIM card so I could get some work done. Don't stay here if you'll rely on wifi to work remotely. We got refunded for 1 night even though we ended up paying more for the first night when were on our own, and for the SIM card to solve our lack-of-wifi-problem.
Mexico City is an absolute wonder and your experience there is what you make of it, so no doubt we had an amazing time despite this glitch. If you plan it right, it's a fairly inexpensive place to be so maybe spend a little more money and stay somewhere else. Or maybe you don't even need to spend more money, but do stay somewhere else.