All you said is “Swapfile is better” and gave no reasons, but linked to the ArchWiki article. The ArchWiki article does not imply one is better than the other in any way, so the link does not support your claim.
How generous of you. 
Next time, start with that so your statements are not so logically disjointed.
How did you make out with the Btrfs balance? 
Anyway this little side-discussion is off-topic so I’ll move it to the appropriate thread.