No. Apple apps in general bypass the VPN, which itself is concerning. The issue with VPNs on iOS is that literally nothing is masked unless you connect the VPN, then turn on airplane mode, wait a minute, then turn it back off so that all fresh connections are then routed through the VPN tunnel. If you just turn the VPN on, nothing is actually being masked because iOS doesn't allow any VPNs to shut down connections from other apps to be re-routed.
Update: Apple does appear to have introduced an (optional) fix for this as of iOS 14, but questions remain –...
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