Actually, this has the most impact on startups that are close to break even or barely making profit. Let's say you make 1m ARR and have 5 software engineers at 200k/year. Prior to this tax code, you had $0 in profit to be taxed. With this change, you can only amortize 10% of software labor in the first year. Now, the IRS treats you as having 900k profit so you have ~200k in taxes to pay.