No, you cannot legally go 30 to 40 mph on a 65 mph speed limit freeway in normal conditions. Speed limits are set by authorities to ensure the safety of all road users, and it is essential to follow these limits for your safety and the safety of others.
In most jurisdictions, driving significantly below the speed limit on a freeway can be just as dangerous as driving above it. It can create hazardous conditions, increase the risk of accidents, and cause traffic flow issues. Driving at an excessively slow speed may also lead to citations or fines for impeding traffic.
If you find that you are unable to maintain the minimum speed or are uncomfortable driving at the posted speed limit, it's best to use alternative routes or roads where slower speeds are permitted. Always adhere to the speed limits and adjust your speed based on traffic, road conditions, and weather to ensure a safe driving experience.