What is a software dev expense and why should it be tax deductible?
If you sell $100 of goods and you have $100 of expenses, you have $0 net income and owe no taxes as a company- you've made no money!
Because software salaries are counted as research and development, and 174 forces you to amortize the expense over five years, you are now in a much harder position:
You sell $100 worth of software and have $100 of developer salaries. You haven't made any money, and you have $0 in your bank account. The government compels you to not expense more than $20 of those salaries, and taxes the remaining $80 of revenue. You are now bankrupt.