Airlines publish a minimum connection time various combinations of airport, terminals and flights. Now I feel that many time it is unrealistic and have been caught by such connections several times, despite doing my best effort to meet the connection. It has happened that my luggage has missed the flight but I managed and vice-versa.
The Dubai airport is particularly large and there are some terminal changes where you have to lineup for passport control which can cost you 20-40 minutes depending how busy it is. Since your example are two international flights, you do not have to pass immigration though and your luggage should be transferred without your intervention. This helps but sometimes they do not notice the tight schedule and the luggage is not transferred on time. Last time I was flying out of Dubai with a 45 minute layover in Bangkok on the way to Hanoi, I mentioned it at the check-in counter and they tagged my luggage with a bright yellow sticker that said "Hot Transfer". It made it and so did I, only just. The gate closed less than 5 minutes after I boarded.
Usually with 90 minutes layover time, unless there was a flight delay, I have never missed any flight. For domestic connection, I usually consider 1 hour enough. As someone said in the comments, if you do miss the a flight, the airline has to accommodate you on another flight but it can be quite a pain and cause other issues such as loss of hotel, missing another flight, boat, train, etc.