Several things here:
(1) It's August, the hottest and most miserable month of the year. Nobody is paying attention to the race right now except die-hard political watchers and the beltway class.
(2) Trump supporters aren't going to be swayed by Hillary's, DNC's, or any other pro-Hillary PAC ads. Their (our) minds are made up - We aren't going to stop our intention of voting for Trump just because some ad says so.
(3) 30-second television ads (and robocalls) are obsolete. If Trump does roll out ads, expect him to roll out short video clips about the issues and his life story. These video clips will be streaming on mobile devices or on home streaming systems such as Roku. Or they'll be ads embedded in popular websites and blogs.
(4) Trump is already famous. He doesn't have to reintroduce himself. People know who he is and those who are curious will do their own research and understand the issues.
(5) Trump's rallies are in the tens of thousands while Hillary is getting no more than classroom-sized audiences. That's his ground game right there - the rallies.
agreed with all or most of that
but please consider....
Hillary’s backers are controlling Trump’s messages now, distorting them savagely....
he can probably only control them if he pays for them.....
also,
there are less than 3 months left to election day
and
MANY PEOPLE VOTE EARLY!!!!!!!!!!!!!!!!!!!!!!!
Romney's strategist thought that way and dragged his feet on ads and organization.
Campaign watchers regard that as a big mistake.
Some people think Trump doesn't need to learn from past experience because there's some vast pool of voters who don't declare themselves for him publicly but who'll pull the lever for him in November.
Barry Goldwater thought the same way. It didn't work out for him.
Plus, the way things are going, by November there will be plenty of long-time Republican voters who get so fed up with the circus that they don't bother voting.