Training to failure or leaving some reps in reserve, which is better?

Hello everyone, I have always been doing 2 reps in reserve in my training. For the first week of training, compound movements are done with 2 reps in reserve, while isolation exercises are done with 1 rep in reserve. Each week, I also gradually increase the weight and repetitions to achieve progressive overload. My progress has been good, but it seems like there hasn't been much change in my physique, which is quite frustrating. As the weight/reps increase each week, I naturally reach complete exhaustion where I can't progress further, leading to a deload.

Recently, I've seen some people advocating for training all sets to failure or only reaching failure on the last set. What do you think, is it a good idea to push all sets to failure in the first week, or should I aim to reach failure only on the last set of each exercise? I'm concerned about affecting recovery, as I fear that going to failure in the first week might hinder progress in the following week.

This is the video I watched today：https://youtu.be/6GHhGtYZLXU?si=RnoWjnPL-ALr8KZ7

Thank you all!