It is just a filter for certain cellular traits. It doesn't filter for many other important traits. A good flagellum doesn't indicate good kidneys. A sperm's existence indicates the father made faithful copies of cells, however the new sperm DNA could be terrible at making faithful copies (ability not proven until after fertilisation).
It also depends on how much of the sperm cell comes from the fathers genes, and how much is generated from the new DNA. I didn't find a clear answer to this but the following indicates that the new sperm cell is at least somewhat generated by the sperm DNA:
Because nucleotide recombinations can occur during meiosis I, the genetic code of chromosomes of gametes can differ from that of somatic parent cells (ie., progeny cells might express cell-surface antigens that are recognized by the host [the father] as foreign and thus be eliminated by humoral or cellular immune mechanisms). Occluding junctions that interconnect adjacent Sertoli cells shield secondary spermatocytes, spermatids, and spermatozoa from autoimmune recognition.
I wonder if there are any organisms where the sperm envelope is made by the dad, and the DNA letter is contained inside?
And I'm completely ignoring the mitochondria (Dad's copy are not passed on so should be mostly irrelevant to sperm selection pressures). I'm pretty ignorant of this whole topic - high school biology only.
It also depends on how much of the sperm cell comes from the fathers genes, and how much is generated from the new DNA. I didn't find a clear answer to this but the following indicates that the new sperm cell is at least somewhat generated by the sperm DNA:
I wonder if there are any organisms where the sperm envelope is made by the dad, and the DNA letter is contained inside?And I'm completely ignoring the mitochondria (Dad's copy are not passed on so should be mostly irrelevant to sperm selection pressures). I'm pretty ignorant of this whole topic - high school biology only.