Anscombe, 33, has been left out while full-back Liam Williams, 33, and number eight Taulupe Faletau, 34, have been recalled to the squad.
Gatland stated he thought the Gloucester fly-half might not make the 2027 World Cup in Australia.
“We’ve spoken about 10 as being the position to develop some strength in depth over the next couple of years, looking short term and long term,” said Gatland.
“We know Gareth has a lot of experience. One of the things we talked about is he’ll be 36 by the next World Cup, so will he be around? We need to develop some options and experience.
“It’s definitely a position of concern and losing someone like Sam Costelow as well probably didn’t help.
“Someone like Dan gets that opportunity to put his hand up and hopefully we can support him and he can go and make the most of it.”
Anscombe joined Gloucester this season after recovering from a long-term groin injury.
“He hasn’t been doing the kicking duties at Gloucester in terms of kick-offs, kicking for touch or taking goals,” said Gatland.
“Over the last couple of campaigns he hasn’t been able to handle that load with the kicking stuff.
“I’m sure he would have been able to do that and we know how experienced he is.”
