Well the Judeo-Christian deity is an intervening deity who's heavily invested in human affairs so there should be detectable effects. Wouldn't healings, personal experiences, visions etc be examples of detectable effects?
I find for the 'first century' with Jesus and his apostles there were healings, resurrections, visions, etc. but once the apostles died off the scene such things came to a stop as per what Luke wrote at Acts of the Apostles 20:29-30.
Now the ' detectable effects ' are these last days of badness as described at 2 Timothy 3:1-5,13.
There it describes the selfish distorted form of love the world now displays which is in sharp contrast to the definition of godly love as defined at 1 Corinthians 13:4-6.
Also, an example of a 'detectable effect' is the international global proclaiming about God's kingdom of Daniel 2:44.
This proclaiming is being done world wide just as Jesus said it would be done at Matthew 24:14; Acts 1:8.
Nothing nor anything can stop that noticible effect going on earth wide.
Even modern technology has made the 'detectable effect' of rapid Bible translation possible so that people even in remote areas can have Scripture in their own mother tongue or native languages thus helping to fullfill Jesus' words.
Because man can't establish Peace on Earth is why God will involve Himself intervening into mankind's affairs by having Jesus, as Prince of Peace, be the one who will usher in global Peace on Earth among persons of goodwill.
Then, we will see ' healing ' for earth's nations as mentioned at Revelation 22:2.
This coming 'healing' is why we are all invited to pray the invitation of Revelation 22:20 for Jesus to come !