Well, they could always license browsers from other vendors, which they will, if things need to go that extent.
> they will manage to use VPN and will find other ways to just use the "normal" software
Are users in Kazakhstan willing to pay extra $5 or more per month for VPNs that respect user-privacy? If not, using free VPNs is going to only make matters worse. In India, where porn is blocked, users typically resort to using Telegram or free VPNs to satiate their desire for it; most wouldn't pay $2 per month for VPNs, even when they could afford it (since $0 VPNs are a click away and unblocks porn for them).