Greatly slowed down internet browsing

Hello,
With Smart VPN, which is supposed to connect to the fastest server, however, I see a dramatic deterioration in internet browsing. In any case, the speed is degraded in a ratio of 1 to 8 or 10 when VPN is activated. I can imagine browsing with VPN to be a bit slower as I have been told, but not to such an extent.
If anyone has an explanation, please enlighten me.

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