All that is probably true, but the thesis has one flaw. While the benefits of sexual reproduction tend to be subtle and become evident only over many generation

All that is probably true, but the thesis has one flaw. While the benefits of sexual reproduction tend to be subtle and become evident only over many generations, its costs are heavy and immediate. But isn't the "flaw" already taken care of: the heavy and immediate costs are very much compensated by the pleasure and high stimulus which are as immediate as anyone who has gone through puberty knows. (And which are not unknown in the non-human part of the animal world either.)