Thats true. We are fouling more and earlier, so opponents dont have the easy buckets in the paint but are shooting fts and wide open threes instead. Which makes our D more ineffective than last years.
You should check again. Till the Christmas game, we gave up over 100 points for 12 continous games, a Suns record for the last 20 or so years. Last year, we were 16th in defensive efficiency (8th in effective fg% defense, gave up the 2nd least fts), right now we are 23rd in defensive efficiency because our opponents shoot more fts per 100 possessions and more 3 point shots. That negates our alleged better paint D.
So you prefer to give up more points per possession this year. If I follow your logic, our offense this year is better because we are scoring more points through the paint then last year. Nevermind that we are not scoring as effectively...
One last point. Using your criteria, ppg and fg%, among the top defensive teams in the league are Charlotte, Denver, Dallas and Miami. If we look at defensive efficiency, the top 6 teams in the league are in order: Boston, Cleveland, Orlando, Lakers, San Antonio and Houston. Pretty convincing, especially when compared with the actual standings, isnt it.