It's still a bad foundation

To be fair, not all of us can be socially competent mentally healthy people who enjoy life and regularly stop to smell the flowers. Some of us just suck, some of us are miserable, so we have to put on a fake persona in order to entertain the other person enough for them to actually give us a chance. In a way, dating is all about entertaining and being entertained.

It's either that or stay lonely.

The better alternative is to work on yourself to become a better person, who is worthy of dating without deception.

You are implicitly assuming that there's some finite amount of work that could make every such person "dateable without deception". While it may or may not be true in individual case, as a general statement it sounds to me more like "well, it's _your_ fault because you didn't work on yourself enough, so you deserve to be lonely".

I think many folks are there for sex, and have no problem faking to get it.

And continuing into the resulting relationships

That is why you are not supposed to marry after first date ;)