The better question would be "is it most optimal?"
They are definitely effective when you do enough progressive overload, Ie. intensity/volume, etc. but then, everything will build muscle to an extent if you have progressive overload in it. That's why we always need to ask ourself "is it most optimal?"
With stuff like weighted pullups/dips and similar, you can't go wrong with them. They are great movements which activate a lot of different muscles. Bodyweighted squats, pushups....mmh, well, let me put it this way. First off, they are harder to overload via weight, unless you put lots of weight on your back or do the bw squats with a vest.
If I can get away with doing (as an example) 3x10 squats with 100kg. You will probably take about 10 minutes to do so and have a volume tonnage of 300kg in 10 minutes. If you want to do the same amount of volume with bw squats you needed to do about 300 repetitions, which would probably take you way longer and in the end, I wouldn't even be sure if this might cause enough stimulus for muscle hypertrophy, which is cause by mainly 3 thing; Mechanical tension, Metabolic stress, Muscle damage.
In the same amount of time you're doing the BW-Squats, you could probably do way more sets squats with a barbell or other exercises targeting the muscles and giving a higher stimulus.

For the question about tempo, recent studies show (for example by brad schoenfeld) that tempo has no significant effect on muscle hypertrophy and might even be detrimental due to the fact that you're muscle getting earlier fatigued and you're not capable of doing more reps, which in the end would cause a higher stimulus for hypertrophy. To make it more clear, what would cause more stimulus. 6 Reps of a given weight with slow tempo or 10 reps for a given weight with a higher tempo? Look at the facts above. Tonnage/Volumen, Mechanical tension, Metabolic stress, Muscle damage.

That being said, look at crossfit athletes. They are jacked. Not really "big" compared to bodybuilders, but still in a good shape. They are doing tons of bodyweight exercises but still remember, they're are doing a lot of barbell compound movements as well.
I'd recommend, that if you're main goal is hypertrophy, sticking with heavy compound movements should be a higher priority then bodyweight exercises, unless you have the possibility to do them weighted.

Hope this helps

I noticed a loss in upper pec mass after about 3 months of not doing weighted pushups ....