All three are great song writers but it's hard to compare Beyonce as a song writer to Pink and Taylor. I enjoy Taylor's songwriting and she has written most by herself which is impressive. However, most of her songs just don't do it for me. Pink uses co writers but you can see she can write amazing if you listen to Rose Ave.

Pink has written about such a variety of topics which shows her skills being able to take things that have happened to her and turn it into a great song. Some of my favorites by her:

Don't Let Me Get Me (self-hate teen angst anthem)
Family Portrait, Run Away (We can see how hard it was growing up in her family)
Respect (feminist anthem 'rap song')
Waiting for Love, Catch me while I'm Sleeping (masterpieces)
Who Knew, Beam Me Up (both make me cry when listening to the lyrics and thinking about people I have lost)
Nobody Knows (a great song about being sad in general)
Dear Mr. President (One of the most risky/bold songs released by a pop girl, Taylor and Beyonce would never)
Long Way to Happy (It makes me so sad to think about what could have happened to her to make her write this)
U+Ur Hand (One of the most clever songs lyrically imo)
Fingers (Where is Taylor's self-loving anthem )
Sober (no comment necessary)
Glitter in the Air (extremely emotional song for me)
Perfect (One of the best empowerment anthems, lyrically imo)
Chaos and Piss (One of the best songs about relationships and a standout on TTAL)
The Great Escape (As someone who knows a lot of people who use drugs to escape their problems and have come close to dying because of it, this song hits really hard and shows how caring she is)

Pink is so underrated and being a mainstream pop star releasing such dark emotional songs that make people feel so many emotions proves how great of a song writer she is. I can't imagine Taylor or Beyonce creating the array of emotions and experiences Pink has created in her music over the past 16 years.

Taylor. P!nk is great too but Taylor has such strong charisma and distinctness as a songwriter that's above her peers IMO.

I don't consider Beyonce in the same category as those, we don't really have material from her to judge from that she's had as big of a hand in writing in as Taylor and P!nk have.

Taylor because All Too Well.

Beyonce

She changed a word of that song.... The original was Smack Into You by John McLaughlin.

I love Beyoncé, but she is not a writer, at all.

Taylor > P!nk >>>>>>>>>>>>>>>>>>> Beyoncé

A little note about P!nk. While she has co-writers listed on every song she write the lyrics herself the vast majority of the time. The others listed are for the melody which is included in songwriting. There are instances where a producer took her base work and fitted it into a song when P!nk hit a dead end and there are times when P!nk sat with someone and lobbed lyrics back and forth.

P!nk is humorous. A lot of her "bad lyrics" are jokes that people don't get. Sarcasm plays a big role in her work. And as a lot of people lack the intelligence to pick up on sarcasm they read it as contradictory or misguided.

Taylor does have a lot of acclaim. But I've always found her songwriting to be perfunctory. Who's to say if that acclaim isn't coming from her huge sales numbers? Because we all know sales play a big role in how an artist is perceived. Unless they're a popular but ultimately vacant act like Bieber. Anyway, the issue at hand is who is the better writing and the answer is P!nk