The Nigerians take on AFCON hosts Morocco in Rabat on Wednesday, looking to continue the prolific form which has carried them to the last four.
They reached the final of the last Cup of Nations two years ago in the Ivory Coast before losing to the hosts, while Iwobi also played in the side that reached the semi-finals in 2019.
But he said a happier environment off the pitch - despite reports of rows with the national football federation over bonuses - was now helping bring out the very best in him and a team in its prime.
"I feel like the difference is the sense of brotherhood, the family environment that we have created for each other," the 29-year-old Fulham star said at a packed press conference in the Moroccan capital.
"Of course, at previous AFCONs we have done really well. The team was so strong, but at the same time, we were young, and we were learning about each other.
"I feel like right now everybody is entering their prime, everyone is doing well for their clubs, and you can see the joy and the chemistry we have when playing for our country.
"It is not just on the pitch, also off the pitch, there is a big unity, we are a big family. It starts from the coach - he has brought that brotherhood."
Nigeria limped through their qualifying campaign for the World Cup and saw their dreams of making it to the finals go up in smoke with a play-off defeat on penalties against the Democratic Republic of Congo in Rabat in November.
That was despite a notable upturn in form following the appointment of former Mali boss Chelle 12 months ago.
"We have always given 100 per cent," insisted Iwobi.
"In the World Cup qualifiers, we wanted to win as well, but it was a difficult moment for us, and we have used that disappointment as motivation to go and achieve something for our country, for ourselves, for our families."
Ndidi suspended
Chelle, meanwhile, admitted that the presence of two recent winners of the African player of the year award in forwards Victor Osimhen and Ademola Lookman made his job easier.
Nigeria are the tournament's top scorers with 14 goals, including four for Osimhen and three for Lookman.
But it remains to be seen how they cope against Morocco without suspended skipper Wilfred Ndidi in midfield - Raphael Onyedika of Club Brugge is a likely replacement.
"We are a group and there are some very good players who are waiting for the chance to show something," said Chelle.
Morocco, Africa's top-ranked nation, will be hoping to make the most of home advantage with a crowd of almost 70,000 behind them at the Prince Moulay Abdellah Stadium.
However, their coach, Walid Regragui, is well aware of the quality in the Nigerian ranks.
"We will need to be strong mentally, but when you get to the AFCON semi-finals, you need to raise your concentration levels, run more to stop Nigeria taking a breather or be able to play with the same impact," warned Regragui.
The man who led the Atlas Lions to the 2022 World Cup semi-finals is under enormous pressure to win the tournament at home and knows there are plenty of critics who will be out to get him if he fails.
"In my country, it's like this - you need to accept that when you are the coach of Morocco," he said.
"Every result you have critics. I stay focused on my team. I fight for my country and the critics every time. What I say to my players is I can't fight about this. What is important is what they do on the pitch."