Sayings of Jurists (May Allah have mercy on them) regarding Qaza-e-Umri 🌟 

1- 
Imam Bukhari narrates the saying of Hazrat Ibrahim Nakhai (May Allah have mercy on him)
وقال ابراہیم من ترک صلاۃ واحدۃ عشرین سنۃ لم یعد الا تلک الصلوٰۃ الواحدۃ
Sahih Bukhari, Vol. 1, p. 84

The person who misses one prayer, even if twenty years have passed, should offer only that missed prayer. 

2-
Imam Ibn Najeem Hanafi (May Allah have mercy on him) says
فالاصل فیہ ان کل صلوٰۃفاتت عن الوقت بعد ثبوت وجوبہا فیہ فانہ یلزم قضاؤھا۔ سواء ترکھا عمدا او سھوا او بسبب نوم وسواء کانت الفوائت قلیلۃ او کثیرۃ
Bahr al-Raiq, Vol. 2, p. 141

The principle is that every prayer that is missed after it becomes obligatory in its time, it is obligatory to make it up, whether a person missed that prayer intentionally or by mistake, or the prayer was missed due to sleep. Whether the missed prayers are many or few. In any case, Qaza is obligatory.

3-
The famous commentator of Muslim, Allama Nawawi Shafi'i (May Allah have mercy on him) says
فِيهِ وُجُوب قَضَاء الْفَرِيضَة الْفَائِتَة سَوَاء تَرَكَهَا بِعُذْرٍ كَنَوْمٍ وَنِسْيَان أَوْ بِغَيْرِ عُذْر
Sharh Muslim lil-Nawawi: Vol. 1, p. 231

It is obligatory for a person whose prayer is missed to make it up, whether that prayer was missed due to an excuse such as sleep, and forgetfulness or without an excuse.

4-
Allama Mulla Ali Qari (May Allah have mercy on him) says
من قضی صلاۃ من الفرائض فی آخر جمعۃ من شہر رمضان کان ذالک جابرا لکل صلاۃ فائتۃ فی عمرہ الی سبعین سنۃ باطل قطعا لانہ مناقض للاجماع علی ان شیئا من العبادات لا یقوم مقام فائتۃ سنوات
Al-Mawdu'at al-Kubra, p. 356
This narration that whoever offers a obligatory prayer as Qaza on the last Friday of Ramadan
 then all the prayers that he missed in his life up to seventy years will be fulfilled, this narration is absolutely false because this hadith is against Ijma (consensus). Whereas there is a consensus on the fact that no act of worship can take the place of prayers missed for many years.

Note: The jurists have clarified that only the obligatory prayers and witr prayers should be offered from the missed prayers, and the sunnah and nafl prayers should not be made up.

And Allah knows best the truth.