What you see in Saudi Arabia is an artificial thing that would collapse sooner or later (especially once petro-dollar finishes). In Saudi Arabia you will find Wahabism imposed over ‘Sunnis’ by ruling class who are Wahabis, even though Most of Saudi Arabians are not Wahabi but Sunni. Most Muslims (Sunnis as well as Shias) do not even consider Wahabis as proper Muslim and staunch Sunni ‘Beralvies’ would not even like to pray behind Imam of Mosque who is Wahabi or even Deobandi. Amongst Muslims, only Deobandis tolerate Wahabis.
Actually, Shias in Saudi Arabia are in much better position than Sunnis, because at least Shias can have their separate religious identity. As for Sunnis, they cannot even practice what they believe.
If Pakistan would start same policy what Saudi Arabia follows, than since Sunni ‘Berelvi’ sect is dominant in Pakistan, Pakistan would have to force on all Sunnis that every person calling themselves Sunni would have to follow Sunni ‘Berelvi’ sect, all mosques would have ‘Imam’ following Sunni ‘Berelvi’ sect, and no one in private or public could talk about any sect (Deobandi, Salafi, Ahle-hadith, or Wahabi) other than Sunni ‘Berelvi sect’. Further, any person breaching this law would get punished by state. Well, state can even execute them by declaring them Mushrik or Kafir.
After Sunnis ‘Berelvis’, Shias are second most dominant sect in Pakistan. Both have little religious differences and both have lived together peacefully since centuries. Anyhow, if Shia person becomes head of Pakistan and strong enough to control armed forces, than they can also enforce Shia laws all over Pakistan and instead of Berelvis we would have enforced Shia sect all over Pakistan
Fortunately, other than Wahabis and Deobandis, no Muslim believe on enforcing their sectarian laws and beliefs over others, and that is why you only see such farce in Saudi Arabia (Wahabi doing that) and Afghanistan under Taliban (Deobandi doing that).
Anyhow, if you like that in Pakistan and willing to accept enforced Sunni (Berelvis) or Shia domination then it is fine, but I am sure that minorities who follow Deobandi sect, Wahabi sect, Ahle-hadith sect, etc would not like that.
[Deobandi sect in Pakistan is 3rd largest but quite influential in middle class Pakistan including armed forces, academia, journalism, and bureaucracy … so, obviously they would react badly if such would happen in Pakistan].