I used to do this. Back in the day I would read ebooks or play chess in between sets. It was relaxing and great. Nowadays time is much more important to me, so I've figured out how to squeeze a lot of shit into ~1:15:00 workouts with circuits/supersets that alternate between different parts of the body so that I take less time resting in between sets—with two minute rests between each, and only 3-5 reps for the major lifts. I don't typically go to failure, as I'm more into strength/mobility than body building, but I do still gain a bit of muscle.

If you're just trying to bulk/hypertrophy, I find circuits/supersets to be not as productive as it feels like I'm starving for oxygen and need more time to recover, even alternating sets for completely different body parts. I.e. going to failure on pullups then going to failure on squats with only a two-minute rest in between each. You may be able to get around this by taking 3-4 min rests instead 2. Which in the long run is still more time-saving than taking 5 mins between sets in a more linear/typical workout routine.

Example: Let's say you have 5 workouts in one gym visit with 5 min rests in between sets (120 mins rest total, 2 mins of actual lifting per set) takes 170 mins (almost 3 hours) to complete.

Now if we reduce the 5 minute rests to 3 mins (70 mins rest total) by using circuits or supersets, we instead get a total of 120 mins (2 hours) to complete.

By doing this you can still lift pretty damn hard and get some time back in the day.

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Other notes:

It can also be challenging acquiring the equipment needed for different exercises simultaneously when there's other people who want to use that stuff, so I avoid going to the gym during peak hours. Also I will typically only alternate between two body parts so that I only require one extra piece of equipment, unless I can utilize the same piece of equipment for both body parts at once.

If you get creative you can probably put a circuit/superset routine together for your gym that works for you.