Just Curious Ji ,
The things which you state about Guru Nanak Dev Ji are in no way in clash with the Religion he founded .
1. Guru Nanak Dev Ji DID marry & bore two sons , he lived a life of house holder not an ascetic .
2. He went to travel whole of the world to preach his faith when he saw the whole world burning in mindless religious bigotry , irrational practices , hating each other due to some false notions of differences .
Bhai Gurdass Ji the great Sikh scholar who helped Fifth Guru Guru Arjan Dev Ji in compiling & editing Sri Guru Granth Sahib Ji , whose Vaars are declared by none other than Guru Arjan Dev Ji himself as the KEY TO GURBANI describes the arrival of Guru Nanak Dev Ji in Vaar1 Pauri 23 as:
Vaaran Bhai Gurdas:- Vaar1-Pauri23--:SearchGurbani.com
Vaar 1 Pauri 23 Coming of the Guru
ਸੁਣੀ ਪੁਕਾਰਿ ਦਾਤਾਰ ਪ੍ਰਭੁ ਗੁਰੁ ਨਾਨਕ ਜਗ ਮਾਹਿ ਪਠਾਇਆ ।
sunee pukaari daataar prabhu guru naanak jag maahi patdaaiaa|
The benefactor Lord listened to the cries (of humanity) and sent Guru Nanak to this world.
Line 1
ਚਰਨ ਧੋਇ ਰਹਰਾਸਿ ਕਰਿ ਚਰਣਾਮ੍ਰਿਤੁ ਸਿਖਾਂ ਪੀਲਾਇਆ ।
charan dhoi raharaasi kari charanaamritu sikhaan peelaaiaa|
He washed His feet, eulogised God and got his Disciples drink the ambrosia of his feet.
Line 2
ਪਾਰਬ੍ਰਹਮੁ ਪੂਰਨ ਬ੍ਰਹਮੁ ਕਲਿਜੁਗਿ ਅੰਦਰਿ ਇਕੁ ਦਿਖਾਇਆ ।
paarabrahamu pooran brahamu kalijugi andari iku dikhaaiaa|
He preached in this darkage (kaliyug) that, saragun (Brahm) and nirgun (Parbrahm) are the same and identical.
Line 3
ਚਾਰੇ ਪੈਰ ਧਰਮ ਦੇ ਚਾਰਿ ਵਰਨਿ ਇਕੁ ਵਰਨੁ ਕਰਾਇਆ ।
chaaray pair dharam day chaari varani iku varanu karaaiaa|
Dharma was now established on its four feet and all the four castes (through fraternal feeling) were converted into one caste (of humanity).
Line 4
ਰਾਣਾ ਰੰਕੁ ਬਰਾਬਰੀ ਪੈਰੀ ਪਾਵਣਾ ਜਗਿ ਵਰਤਾਇਆ ।
raanaa ranku baraabaree pairee paavanaa jagi varataaiaa|
Equating the poor with the prince, he spread the etiquette of humbly touching the feet.
Line 5
ਉਲਟਾ ਖੇਲੁ ਪਿਰੰਮ ਦਾ ਪੈਰਾ ਉਪਰਿ ਸੀਸੁ ਨਿਵਾਇਆ ।
ulataa khaylu piranm daa pairaa upari seesu nivaaiaa|
Inverse is the game of the beloved; he got the egotist high heads bowed to feet.
Line 6
ਕਲਿਜੁਗੁ ਬਾਬੇ ਤਾਰਿਆ ਸਤਿਨਾਮੁ ਪੜ੍ਹਿ ਮੰਤ੍ਰ ਸੁਣਾਇਆ ।
kalijugu baabay taariaa satinaamu parhhi mantr sunaaiaa|
Baba Nanak rescued this dark age (kaliyug) and recited ‘satinam’ mantr for one and all.
Line 7
ਕਲਿ ਤਾਰਣਿ ਗੁਰੁ ਨਾਨਕੁ ਆਇਆ ॥੨੩॥
kali taarani guru naanaku aaiaa ॥23॥
Guru Nanak came to redeem the kaliyug.
I request you Just Curious ji to go through whole of Vaar 1 which will take only perhaps forty five minutes to have some clarity on the purpose of Guru Nanak Dev ji's life & whole of background regarding the origins of SIKH FAITH rather than listening to somebody's half-baked LOGIC or one-sided statements . Sikhism is very very unlike any of the previous philosophies this earth has known in last 3500 years .