Right... but the femur is almost twice the size of the brachiosaurus' femur but "most of the increased length is in the neck and tail." Again you make a statement claiming sources but NEVER PROVIDE THEM. POST THEM. I've posted many sources, you've posted none.
And SO WHAT??? Even if the length is in the tails and necks and the proportions have been mis-interpreted, these animals are STILL too large for the ability of their muscles to carry them.
From left to right:
The diplodocid Seismosaurus hallorum (skeleton on display at the NMMNHS–33 m. (110 ft.) long),
The diplodocid Amphicoelias fragillimus (est 58 m. (190 ft.) long),
Homo sapiens (1.8 m. (6 ft.) tall),
African Elephant Loxodonta africana (4 m. (13 ft.) tall at the shoulder),
The titanosaur Argentinosaurus huinculensis (est 30 m. (98 ft.) long),
The titanosaur Puertasaurus reuili (shortest reported estimate 35 m. (115 ft.) long).
Note that, in this latest estimate, Seismosaurus completely fits under the tail of Amphicoelias fragillimus!
Reconstructed Seismosaurus Hallorum on
display at the New Mexico Museum
of Natural History & Science,
110 feet long, estimated
weight 160,000 - 200,000 Lbs.
Do you want to start calculating the amount of strength a muscle would have to have to keep those necks and tails off the ground, cantilevered out over 40 feet?
And as shown earlier, one sauropod, the Brachiosaurus, for which we have a complete skeleton, is estimated to weigh in at 70-90 thousand pounds... two to three times the theoretical maximum weight that muscular strength can lift against 1G.
Are you arguing that these animals never existed or that they somehow had Kryptonian super-powers?