Proposals in the Digital Britain report will transfer billion of pounds to old companies and tax the very companies it claims to want to help, says Microsoft UK's former national technology officer.
Jerry Fishenden, who left Microsoft last week after 12 years with the software firm, said the report puzzled him. Will taxing broadband users encourage them to adopt the technology? he asked.
"I suspect many people will opt for their mobile phones. A lot will depend on what content they can get from fixed broadband," he said.
Communications minister Stephen Carter announced last week that the government would introduce a tax of £6 a year on fixed-wire phone lines to help pay to upgrade network speeds.
The government plans to use £200m left over from the digital switchover of television broadcasting plus matching funds from industry to extend 2Mbps network access to all households by 2012, Carter said.
But Fishenden questioned whether the tax, which will raise an estimated £175m to £250m a year, will be enough to deliver "superfast" network access to 90% of the population by 2017.
The Broadband Stakeholders Group, a supplier-led lobby group, estimates it would cost £5.1bn to install fibre to the kerb (FTTC). This would provide a top download speed of around 40Mbps to 50Mbps to homes.
But Fishenden doubted whether the core UK infrastructure could cope now or in future with growing demand for bandwidth.
Fishenden said very few people wanted superfast or even high-speed broadband all the time. "When I want to download a high definition film I want all the bandwidth so that I can get the content in five seconds. But I don't need it after that, while I am watching the film," he said.
The answer was to supply bandwidth on demand for both downloads and uploads because more people were using video for phone calls and teleconferencing, he said.
Countries such as Japan and South Korea plan to have fibre to the home capable of delivering at least 100Mbps, with 1Gbps in future.