Apart from maybe the impregnation of Vala, that is a slight hint towards Jesus, is there any mention in Stargate SG-1 of the modern gods that are known to mankind today, such as the deities behind Christianity, Hinduism, Buddhism or Islam?
I can only, for certain, account for Ancient Egyptian gods, Norse gods and Slav gods (Svarog).
For a very good In Universe reason.... most of those religions weren't (AFAIK) established until after the Goa'uld had left Earth in 3000BC.
The episode Mobius established that SG1 helped oust the Goa'uld from Earth by travelling in time to 3000BC using a Puddle Jumper.
In addition, the religions described (he says carefully) would not fit the Goa'u'd methodology. Teal'c says...
I know of no Goa’uld capable of showing the necessary compassion or benevolence that I have read of in your Bible.
However, as has been pointed out in comments various religions that came into existence after the removal of the Egyptian stargate are referenced, including Hinduism, Shinto and, by implication Christianity.
Whether the Goa'uld were the inspiration for these "gods" or just assumed their names is unclear though.
For instance: Christianity
The medieval Christian beliefs of the humans means that their ancestors must have been taken from Earth after the first council of Nicaea in AD 325 that established the said belief system and likely after the fall of the Roman empire and into the Dark Ages given their belief in demons, which makes it highly likely they were the last group of humans to leave Earth until the rediscovery of the Stargate and Dr. Ernest Littlefield's 1945 trip though the gate and the last group of humans ever to be taken off-world as Goa'uld slaves. Since this puts their departure well beyond the known date of the rebellion against the Goa'uld, especially after the alternate SG-1's involvement in "Moebius, Part 2", they were likely removed via ships...or via the second Stargate in Antarctica as it was stated the Goa'uld used it and as evident of the two Jaffa they found frozen there.
In season 3 episode Demons they encounter a medieval Catholic society.
Carter: The UAV photos were right, there it is. Looks like a church.
O'Neill: And that would mean what?
Teal'c: That it is most likely Christians reside here, O'Neill. [...]
Daniel: Which means they probably had to have been taken from somewhere in medieval Europe through the Antarctic gate.
At first, they think the Goa'uld is playing the Abrahamic God
Daniel: Well, if these people were already Christians when they were taken from Earth, that suggests this Goa'uld is…is playing…
O'Neill: God? As in God God? It's a bit of a stretch, don't you think?
Teal'c: I know of no Goa'uld capable of showing the necessary compassion or benevolence that I have read of in your Bible.
The people feared a demon (Unas) who was a servant of the devil (Sokar).
Unas (in a distorted, Goa'uld-like voice): The time of Sacrifice is at hand. My lord Satan calls for five wretched souls to reclaim as his.
Recurring character Nirrti was also the Hindu goddess of 'deathly hidden realms and sorrows'.
Does Satan count as a "modern god"?
If so, then there's Sokar.
Islam, Christianity and Judaism have the same god. I doubt any Goa’uld would dare mimic him, as he did kill the first born son of all Egyptians under the rule of Thutmose II. See this Quora post.
I also would remind others that Hinduism is almost as ancient as God, 4000 years instead of 5000 years.
And that no Goa’uld would be patient enough to be Buddhist. Perhaps Tok’Ra created Buddhism in SGU?
As mentioned previously, unequovocally yes. Teal'c specifically states that no Goa'uld would have the benevelence to mimic the Christian God. Additionally there is an implicit racial bias towards the Gods of SGU. All of the Goa'uld (not Tok'ra) draw their names from non-white non-judeo-christian origins, while the good guys draw their inspiration from white religious ideas. The Asgard are drawn from the Vikings of the Scandinavia, the Nox draw their inspiration from the Sidhe of Celtic/Gaelic traditions in that they are immensely powerful, secretive and desire only to be left alone and in harmony with nature.
