What could have started with a genuine experience of God moved on to something that clearly wasn’t of God. Man has a tendency to take things into his own hands and try to control them; to make them work at will, turning relationship into procedure, hoping to bring about an expected outcome on demand.
Laughter in a church context was around long before Toronto (there are several historical examples). It also happened in a church that I used to attend. I was there from the late 70s and most of the 80s. The laughing happened before I had joined them and it wasn’t widespread. It affected a small number of people and it was seen as a spontaneous outpouring of joy from young, new believers. No one tried to make it into something that ought to be experienced by all.
Things may have worked out differently if the church leadership had turned their focus onto the laughter and had encouraged everyone else to join in. Maybe the “Toronto blessing” would have come two decades earlier (in the 70s) and be known as the “Wollongong Blessing”.
But I think there were some big changes over the next two decades that made the Pentecostal/charismatic church more open to exaggerating those experiences beyond any initial Divine involvement. It probably couldn’t have gone to the same extremes (and so widespread) in the 1970s or before.
These days NOTHING done by “Christians” and claimed as the work of the Holy Spirit would surprise me. While Toronto itself may no longer have the same prominent profile, it spawned several influential descendants who continue to spread a gospel different to the one preached by Jesus and the apostles. Those churches accept and promote all manner of new and not so wonderful things, attributing them to the Holy Spirit even when those thing are at odds with His character – note: there’s a clue to His character in His name.