how can l-values be passed to std::make_pair

In std::make_pair there is only one implementation C++14 onwards

template< class T1, class T2 > constexpr std::pair<V1,V2> make_pair( T1&& t, T2&& u );

Both parameters are R-value references and according to this

R-values references cannot be initialized with l-values.

    int i = 1;
    char ch = 'a';
    std::unordered_map<int, char> mp;
    mp.insert(make_pair<int,char>(i, ch));

So when I try to use make_pair as in the above code it correctly throws an error error: cannot bind rvalue reference of type 'int&&' to lvalue of type 'int'.

However it works perfectly for the above code if I change drop the template arguments and call it as

mp.insert(make_pair(i, ch));

I'm confused how this works as i and ch both are L-values. Does template argument resolution convert L-values to R-values or like how does this work?