Generally...
Why should Christians trust what anti-christians say? Especially when those anti-christians are saying things that would benefit those same anti-christians.
Specifically about 7 days versus 7 years...
I don't claim to know which is correct.
I Believe Scripture Is Very Clear On The 70 Weeks, They Are Literal And Future, And Will Be The Sign And Warning Of The Pending (Man Of Sin/Antichrist) To Follow
Daniel 9:24-27, Seventy Literal Weeks Explained?
Daniel's 70 weeks are literal 7 day periods, or 490 literal days.
If Daniel meant 490 years he would have written
(Four hundred and ninety years), simple
Daniel had no restrictions in "Writing" exact numerology as seen below.
Daniel 6:1KJV
It pleased Darius to set over the kingdom
an hundred and twenty princes, which should be over the whole kingdom;
Daniel 8:14KJV
And he said unto me, Unto
two thousand and three hundred days; then shall the sanctuary be cleansed.
Daniel 12:11KJV
And from the time
that the daily
sacrifice shall be taken away, and the abomination that maketh desolate set up,
there shall be a thousand two hundred and ninety days.
Below in Daniel 10:2-3 we see just another example of Daniel's literal weeks, as Daniel mourned and fasted for 3 literal weeks or 21 days.
Daniel 10:2-3KJV
2 In those days I Daniel was mourning
three full weeks.
3 I ate no pleasant bread, neither came flesh nor wine in my mouth, neither did I anoint myself at all, till
three whole weekswere fulfilled.
Below in Daniel 9:24-27 we see 70 literal future weeks or 490 days.
When the call/commandment goes out in Jerusalem to build unto the Jewish Meshiach/Messiah that they wait for (They Denied Jesus Christ) this will start the 7 week period.
62 literal weeks will be in building, and Meshiach/Messiah will be cut off by the Antichrist who stops the building.
The 70th literal week will see the antichrist revealed in making a covenant, and in the middle of this literal week he proclaims to be Meshiach/Messiah God to the Jews, and Jesus returned to the apostate church, to start a Millennium on earth.
The 3.5 year tribulation has started.
Daniel 9:24-27KJV
24
Seventy weeks are determined upon thy people and upon thy holy city, to finish the transgression, and to make an end of sins, and to make reconciliation for iniquity, and to bring in everlasting righteousness, and to seal up the vision and prophecy, and to anoint the most Holy.
25 Know therefore and understand,
that from the going forth of the commandment to restore and to build Jerusalem unto the Messiah the Prince
shall be seven weeks, and threescore and two weeks: the street shall be built again, and the wall, even in troublous times.
26 And after threescore and two weeks shall Messiah be cut off, but not for himself: and the people of the prince that shall come shall destroy the city and the sanctuary; and the end thereof
shall be with a flood, and unto the end of the war desolations are determined.
27 And he shall confirm the covenant with many for one week: and in the midst of the week he shall cause the sacrifice and the oblation to cease, and for the overspreading of abominations he shall make
it desolate, even until the consummation, and that determined shall be poured upon the desolate.