The House proposed no money for high-speed rail. The Senate proposed $2 billion. So what do they compromise at? $8 billion. Plus Amtrak gets $1.3 billion, which is also more than in either the House or Senate bills.
Highways and urban transit get the amounts in the Senate bill, $27 and $8.4 billion, which is less than the House bill. Since the total for transportation is $46 billion, that leaves about $1.4 billion for airports.
Just where are they going to find $8 billion worth of shovel-ready high-speed rail projects? Not in California, where I doubt they will be ready to begin construction for another couple of years.