“If it were up to me I would just (follow) whatever decision the USGA comes to”
Last November, the R&A, which was set up as a distinct entity separate from the Royal and Ancient Golf Club in 2004, and the USGA proposed a ban on players anchoring putters to their body to help preserve the "skill and challenge" of putting.
Players and the golfing community were then given 90 days, until 28 February, to discuss the plan.
But Finchem's comments, that there is "no overriding reason" to ban the putters, raise concerns about different rules emerging in different competitions.
"I saw what Tim Finchem had to say and it seems like the European Tour is going to go a different way," said world number one McIlroy, 23.
Players using long-handled putters anchor strokes to a pivot point, such as their chest or midriff, and three of the past five majors have been won by those using that method.
But McIlroy, who uses a conventional putter, says he would not have an issue if long-handled putters remained being used in the sport.
"It's up to the governing bodies at the end of the day to decide," added McIlroy, ahead of his defence of the Honda Classic in Florida starting in Thursday.
"I sort of think it was a bit of a knee-jerk reaction to how much success people were having with it.
"I'm all for people enjoying the game and trying to make the game as easy as possible and bringing people to the game, and if that means they should allow anchored putters to make it easier for the general public then that's a good thing.
"But then they talk about bifurcation, whether you should have one set of rules for us and one set for the amateurs and it's just a bit of a mess and opened a can of worms.
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