Softbank-owned Arm reported declining revenues and narrowing profits in its IPO filing last night, bringing into question whether Softbank founder and CEO Masayoshi Son will be able to pull off what’s expected to be the biggest U.S. debut this year. Son has said he wants Softbank to lead the AI revolution, with Arm as its biggest driver. But just how central is the chip designer to the revolution anyway? Its own filing said that its processors may not be suitable for AI purposes, and its biggest market, smartphones, is in decline.