The question regarding whether a truck driver can get or deduct per diem is all based on how you are treated with the company. If you are an owner/operator, receive a 1099, and subcontract through the trucking company then you would still be eligible to deduct per diem based on the federal standards.
On the other hand, if you are an employee of the company, you get a W2 at year end, the Tax Cuts & Job Acts did away with un-reimbursed employee expenses. Meaning that as an employee you are not eligible to take that deduction.
Also be careful on how or if your employer pays you per diem. If your employer pays you per diem to be on the road, that money could be taxable to you the employee. The employer has two options when it comes to per diem, an accountable plan, and a non-accountable plan.
With the accountable plan your employer pays you per diem to be on the road and they hold you responsible for turning in all receipts and any unused money on your return, hence you are accountable for all the money. The receipts are a deduction for the company and do not affect you the employee.
With the non-accountable plan, your employer pays you to be on the road and you are responsible for all receipts, you turn nothing into the employer. The per diem is taxable to you as an income, but you are not allowed to write off any expenses due to the Tax Cuts & Jobs Act.