Not in my opinion. Generally what you are hearing is the processed sounds of Autotune IMO.

Both the above and more. No rules really but we all know how popular Autotune is. Like reverb and delay, Autotune is a culture and also part of the standard sound of Top 40.

Filters, compressors and harmonizers are cool sounding too.

I'm not in that part of the business, so I can't add any inside info. But I definitely agree that a lot of the "Clear Channel Ready" pop sounds heavily processed. However, one thing I've learned is never to try to guess the actual techniques used to do processing (at least in public.) There are a million ways to get something similar to these effects, and as soon as you guess it's A someone will pipe up and say it was B. (They might be lying. No one wants to give up secrets.) So, yeah. Double tracking, pitch correction, time correction, reverb, delay, chorus, flanging. Listen to what people say they are doing (knowing you'll rarely get the full truth.) Try stuff. Try some more stuff. Eventually you will get there.

One thing I DON'T think is happening much these days is double tracking. It was very popular up to 20 years ago in the absence of the the effects that are so widely available today, but these days you only tend to hear it in moderation, as an extra effect.

Nowadays it's all about that very dry and upfront vocal. I love it. You can definitely hear it on Taylor Swifty's production. Even in the choruses it seems like the one vocal surrounded by quite a few backup harmonies. I think the trick is they somehow they can get it to fill more than just dead center stage. Wish I knew how!

I think now in more electronic oriented pop choruses that you're more likely to find the double tracks, but maybe I'm just going off the songs that I know

Both the Dangerous Music 2-bus and SPL MixDream have mono switches that are indispensable. They dead center bass, kick, snare and lead vox like nothing I've ever used. thumb

Double tracking a vocalist was always a good way to improve the perception of a vocalist who couldn't cut the mustard soloing. You listen to them after their first pass and you go UGH, let's try for a second take. Then you combine both of the awful to make less awful with. And then it sounds cool. You must be listening to some pretty peculiar music to think that everybody is double tracking their vocals? Everybody is definitely NOT double tracking their vocals.

I don't want to repeat myself again.
Mx. Remy Ann David

I don't want to repeat myself again.
Mx. Remy Ann David