Fair points, though you're leaving out free throw shooting; Marcus was much better at getting to the line than Avery, and shot grade-A from there (one reason they posted him up so much)
.
Defending a guy that shoots 35% from the field and 28% from the three can't be easy.\
And yet he gets to the line - a lot - anyway.
He shot a free throw for almost exactly every three FG attempts last season (.334, an excellent number; compare to Avery at .120) - and he doesn't use a whole lot of possessions.
Most casual fans aren't including FT shooting when they talk about "shooting", but it's a good way to score points, and Marcus, in addition to taking a lot of trips there, is money when he does: .812 last season, which is grade-A.
That helps the team get in the penalty, so that Isaiah and Jaylen can shoot more free ones, too. Casual fans focus on shooting and scoring, and are less aware of how a player impacts the whole offense of the team.
If he's going to continue to facilitate out of post-ups, he simply has to get better at putting the ball in the basket. Casual fans are more focused on his 3-pt shooting, but he was dismal at the rim: .488 is godawful.
The ability to get to the FT line and the way it enhances the efficiency/value of a player's scoring attempts is captured in TS% (which is called "True Shooting" but really is a measure of _scoring_ efficiency, not shooting efficiency).
Yes, it's a valuable stat. But it's also valuable to break it down into its components, to look for the areas that need improving, and to assess what might be possible in the future. FT shooting%, for example, is a steadier stat year to year, while 3-pt. shooting% is highly variable.
Look, I like Marcus and I want him to succeed as much as any Celtic fan. And I don't want to give up and say their is no hope for his offense.
I'm going to get on my hobby horse again: FG shooting is only one part of offense. TS% is a bigger part, but still only part of offense. Marcus is already a plus on offense
as a whole, despite his woeful true shooting percentage.
Modest improvements in his FG shooting would make a big difference - but, as I pointed out above, what he really needs to do is take better care of the ball. If you miss a shot, there is at least a chance at an offensive board - but turnovers are lost possessions.
The roster has changed. They'll be running a lot of offense through Gordon Hayward, who makes plays for teammates and has a low turnover%. They'll be running offense through Jaylen Brown, who as a rookie already had a lower TOV% than Marcus. I think that this means that Smart has got to get more efficient.
But there is really no point to arguments that try to waive off how bad his scoring offense has been. It has frankly, been truly, truly horrendous and denial of that reality is silly.
Well, it wouldn't be the most critical part of our society that is suffering from a denial of reality.
In fact, I pointed out his free throw shooting to put a dose of reality in the discussion. And good free throw shooting is a sign that there is hope for improvement in Marcus eFG%. The results so far should have fans temper their expectations, however. Reasonable goals are:
35% 3-pt. shooting (reasonable, given his corner %s);
.550 at the rim (a stretch, but not unreasonable, given his .517 in the back half of the paint)
12.5 Tov% (reasonable, given that he was at 11.7% the year before).