Does that mean that God's love is universal, or does it mean that God's love is eternal, or does it mean that God's love is omnipotent? The three are mutually exclusive if anyone, even Satan, goes to Hell. We know that Satan will go to Hell, so one of the three must be incorrect.
"God is love," is a poetic statement, which means that there is no denotative meaning. We can't use it to definitively make a logical argument.
Similarly, we might argue:
God is love.
Love is blind.
Therefore God is blind.
Both arguments are poetic, and the conclusion is therefore irrational.
God keeps a record of wrongs. Otherwise he could not judge anyone for anything. If anyone is judged, and if love keeps no record of wrongs, then we cannot assume that God loves everyone.
By analogy:
Dinner is food.
...but my dinner is not your food.
Revelation 21:27
"But there shall by no means enter it [Heaven] anything that defiles, or causes an abomination or a lie, but only those who are written in the Lamb’s Book of Life."
It has nothing to do with the way we judge others.