It's at about the right level, but the distribution is currently a bit skewed.
Anyone who thinks immigration is too high (and dare I say it, probably thinks that ANY immigration is too much immigration) doesn't understand the disastrous effect that a declining population has on an economy.
Somewhat hilariously... it's usually the same people who want immigration who ALSO think that people should only have children after their careers have taken off. So we don't want immigrants... but we also don't want too many people having children
. Hmmmm OK.
You're going to have to choose I'm afraid. Accept more immigration, or encourage young adults who are already here to get breeding and support them in doing so. You CAN'T advocate for "neither". The economy would implode.