Do men like head better than the sex act itself?
By “the sex act itself”, I assume you mean penis in vagina sex (PiV), what many people call “regular sex” or “intercourse.” Like any other kind of sexual preference, it really depends on the man. Sex can be a combination of many things and often good sex is more than just whatever results in orgasm, but a variety of acts that the partners enjoy together, whether that is PiV, oral, anal, manual (a hand job) or something else.
I dated a man who can only orgasm with oral sex (head) unless he knows his partner really, really well (years) and even then it is hit or miss. He and I would have PiV sex because I really like it and then I would give him oral sex to orgasm because I enjoy giving head. He also found getting a hand job equally fulfilling and orgasmic, so that was something he often enjoyed with other partners who did not enjoy giving oral sex. Likewise, he commonly pleasures his partners with oral or manual (hand) sex.
A number of men I know like them equally but differently. Many of them report that they can enjoy themselves and control their orgasm longer with oral sex. So they can have an enjoyable bout of oral sex, followed by an enjoyable bout of vaginal (or anal) sex. Other men really enjoy oral or vaginal sex, but find it easier to orgasm from hand jobs (manual sex.) I should add that I’m talking about mature men who are past the point of wham, bam, thank you Ma’am (or Sir) and (heading) into the years where erectile dysfunction become at least an occasional reality.
I have also had men tell me that after they have orgasmed, or if they are otherwise unable to get erect, they can still enjoy oral sex when vaginal sex would require an erection. I will note that as someone who has a mouth and a vagina, my mouth muscles tend to get sore more quickly than my vagina and pelvic floor muscles which can take a lot more. (And I’m speaking as someone who needs pelvic floor physical therapy!) That said, muscles are muscles and their strength can improve with practice.
Note: It is not strictly true that penis / vagina sex requires an erection. There are a couple of strap / wrap devices to allow penetration without an erection and there is a process called stuffing. But we can certainly say that those are a different kind of sex, super fun sex though!
Image attribution: Ramdlon