Most of that doesn't matter for two big reasons. 1: Manu wasn't 37 4 years ago, so his stats outside of last year don't mean a god damn thing. You can throw everything Manu did outside of last year right out the window because he isn't magically going to get several years younger for those stats to be relevant anymore.
Secondly, how bad Manu actually is is somewhat hidden by the fact that he's on a good team. Monta Ellis played for a ty team which means his stats (percentages mostly, which is all you posted) are going to be worse because not only is the defense keyed on him but he has little help.
Manu is surrounded by good shooters and defensive gurus on a team with a great system where he doesn't even have to play very many minutes, and when he does it's against a ty second unit most of the time. Ellis has only played for ty teams. Offensive and defensive ratings, while nice, more reflect the team they're on than the player themselves. The Spurs as a team have an offensive ratings 5 points higher than the Bucks. Last year it was 6 1/2 points higher. With the Warriors, the Spurs had a 3 points higher offensive rating, but the team at least wasn't awful, which is why Ellis' offensive rating was higher with them.
Speaking of Manu's age and skill regression, notice how even the stats you cherry picked because those were the main (possibly only) stats that were in Manu's favor, all regressed to the lowest points in Manu's career since his first and second seasons. A trend which at best we can hope stops rather than continues.
Instead of cherry picking stats which benefit Manu, let's look at all of them.
Games missed since 2011:
Ginobili: 56Ellis: 6
Turnovers per 36 last year (Ellis plays more minutes, so this is more fair than per game stats):
Ginobili: 3.4
Ellis: 3.0
Minutes played, Ginobili/Ellis:
'10: 28.7 vs 41.4
'11: 30.3 vs 40.3
'12: 23.3 vs 36.6
'13: 23.2 vs 37.5
Btw, Ellis led the NBA in minutes in '10 and '11. Manu wasn't even close.
Turnover % Manu/Ellis:
'12: 16.3 vs 13.2
'13: 17.3 vs 13.7
Oh and Manu's playoff stats:
'12: 17.0 PER
'13: 16.5 PER
'12: 19.8 Turnover%
'13: 19.4 Turnover%
'11: 3.5 TOs/36
'12: 3.9 TOs/36
'13: 3.6 TOs/36
'11: 107 Offensive rating
'12: 106 Offensive rating
'13: 102 Offensive rating
Notice the trend of tier PER, tier offensive ratings, increased turnovers.
Yeah, so not only is it not out of the question to expect Manu to be even worse, but it's not out of the question to expect more from Ellis if he got to play in the cushy, king-like mid 20s minutes per game situation Manu has been in rather than have to be a in 40+ minute per game workhorse for ty teams running their offense and taking the brunt of the opposing team's defensive attention all game.
I'd happily take my chances with the 27 year old Ellis with huge room for improvement considering the great and much easier than what he's used to situation he'd be inheriting here, rather than an aging player who's nowhere near what he used to be and completely let his team and Spurs fans everywhere down in the Finals. Yes, he WAS great. Years ago. Now he isn't. Now he's steadily declining and openly talking about how he hates rehabbing and wants to hang it up.
Feel free to post more stats of years ago though. As if your argument is if we should trade current Ginobili for Ginobili from years ago. Anyone would, but it isn't a possibility. It's current ty Manu, or take a shot on a 27 year old athletic player who can both easily take Manu's place or fill in for Parker should disaster strike.
Ellis adds more potential to the team. Definitely has holes in his game (bad defense for starters), but his offense and ballhandling aren't things I'm very concerned with. His efficiency would clearly go up if he got Manu's role, and at least he wouldn't have to guard stars for 40 minutes a game anymore.
Manu is just getting worse and played worse and worse as the postseason went on last year. PER went down, efficiency went down, GameScore went down (really far down), turnover% went up. Just about everything got worse and worse, until he finally sucked 5/7 games including a huge disaster game in game 6 which cost us the le.