I haven't gained much muscular weight over the last couple years, but I've trained to failure even less than that. If reaching failure were required for growth, then the few times I have failed would be solely responsible for several kilos of learn body mass.
I used to train to failure all the time. I also used to be a lot weaker than I am now. I've found that stopping just shy of failure ingrains the mental point: "I can do xyz," while regularly going to failure ingrains the message: "I cannot do xyz." On the one hand, this makes it all the more exciting when I succeed at xyz, but it also creates inhibitions that prevent me from doing xyz. So I think, if for no reason other than mental, it would be better to generally stay away from failure.
On the other hand, with the help of spotters, I've gone well and truly past the point of failure (eg doing 3-5 negatives with assistance on the positive after volitional failure) back in the day, and the results of that have mostly been good.