He did more than declare he wouldn't deport those whose deportations he has already stopped pursuing. He's giving millions work permits.
These permits will allow them to obtain Social Security numbers and get driver's license from states that were holding the line and not giving driver's licenses to illegals.
This will both allow those illegals to take more jobs from Americans and make it easier for them to receive welfare benefits and direct cash payments from the IRS without paying income take (Earned Income Credits and Child Tax Credits).
“without paying income take” = “without paying income taxes”