Holloway has come in for criticism from some fans after taking over a Palace side looking a good bet for automatic promotion in November, only for them to just hang onto a place in the top six on the final day of the season.
But the Eagles put their dodgy spell of form behind them when Wilfried Zaha's brace secured a 2-0 semi-final win over Brighton and a Wembley date with Watford a week on Monday.
"I couldn't be more pleased for him," said Parish.
"The bad run almost formed him because I think he decided he might as well be himself.
"It's very difficult coming into a successful club and I think he was walking on eggshells and standing on ceremony a bit.
"They've come together as a group. I think the fans are getting to know Ian a bit so I'm pleased for him because he did go through a sticky patch and he did get a lot of stick.
"He's a man and that's what men do, they come through it and he was very strong in that period.
"We had lots of conversations and he never wavered from his philosophies and he's got his just deserts."