So, looking at the opening day 40 man rosters (and players on 60-day IL and restricted lists)...
696 of 1,251 players were drafted and signed out of the 1st to 10th rounds (55.6% of all players on 40 man rosters)
121 of 1,251 players were drafted and signed out of the 11th to 20th rounds (9.7%)
51 of 1,251 players were drafted and signed out of the 21st to 30th rounds (4.1%)
20 of 1,251 players were drafted and signed out of the 31st to 40th rounds (1.6%)
2 of 1,251 players were drafted and signed out of the 41st or later rounds (0.2%)
17 of 1,251 players failed to be drafted and signed as Non-Drafted Free Agents (1.4%)
344 of 1,251 players were drafted and signed as INT Free Agents (27.5%)(3/4ths of whom come from D.R. or VEN)
It's abundantly clear that two things have occurred over the past 20 years or so. A.) Teams are uniformly getting much better at evaluating amateur talent and projecting who will make the bigs, and B.) Draft picks after the 20th round (and more emphatically after the 30th round) were being spent either on true minor league filler (I.E. never making the 40 man roster) or being spent on players who were not signing after being drafted (primarily highschool kids).
So, for all the doom and gloom that some have expressed on a smaller draft; it certainly appears that it'll have very little impact on future big league talent. Future 40 man roster players are still going to get drafted in the smaller drafts. Some of the minor league filler that was being drafted in later rounds will now be signed as NDFA's. And premium highschool players with full-rides are still well more inclined to take that ride to the collegiate ranks if not drafted in the first 10 rounds or so. In fact, it looks as though it would have impacted only about 73 of the 1,251 players or 5.9%. And for all we know those 73 players may have all been (or most were) huge overslot signees - the Reds very own Sal Romano and Amir Garrett are included in that total. Those players in the new format would have likely just been drafted earlier by the teams that ultimately took them.