Probably because he is a failure. Here's a list of reasons why.
1: Praised as one of the most gifted and unmatched shinobi's by A and Jiraiya, yet all of his techniques are stolen excluding rasengan.
2: Failed to kill Obito in his fight which would of been simple since he had him marked. He could of stabbed him in his heart or cut his throat for example.
3: Failed to protect his wife from the kyuubi by transporting it to her after bunta was summoned on top of her.
4: Failed to protect his son against black zetsu and therefore causing him to die.
The list goes on and on. Outside of saving the SA twice and shooting the wad out that became Naruto, he's pretty much a failure with stolen techniques.
Well this is something someone who only look at the cover would say
Talking about genius?
1- He copied Hiraishin sure, but the part you miss here is he developed it on his own without help despite living in a complete different era than Tobirama, making it better and even creating useful variants
2- He learned Uzumaki sealings from her wife, but the part you miss here is he learned hereditary Uzumaki specialised sealing techniques despite not possessing a known bloodline
3- He created rasengan just by observing tailed beast Bijudamas
May i continue?
3- He is also the only one in the entire manga since Haku capable of one-handed handsigns
4- His one-handed Bijuu extracting and sealing skills can be done in an instant when it required 3days for the entire akatsuki to extract Bijuus
5- He can use every types of chakra:
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6- He can become a perfect host of the strongest Bijuu in an instant when it was considered impossible for most and required decades for Naruto to be able to
Just to name some and the dude is barely in his twenties
Also you mention the fact he should have killed Obito, but do you forget the village was in danger? If he didn't come up even a second earlier, Hiruzen and co would have mopped the ground by Kyubi's Bijudama