AGI isn't necessary to completely change things. The change that's occurred in the last 6 months alone is massive. Another couple of big steps like the end of last year and the world is unrecognisable from even a few years ago.

What makes another couple big steps like that inevitable in a short time frame?

Before the recent floodgates cracked open, AI research made only slow incremental progress for decades. Why couldn't we already be back near that rate of progress?