Do you agree the pronunciation of "Steak" is equal to "Stay" plus "k" sound at the end?
The work has been done. The dictionary writers have already asked people such as are on this forum how they pronounce 'steak' and other words. If, in the real world, native speakers pronounce it some other way, then the dictionaries will note this.
That is part of the function of a dictionary.
In some British regions, there is a stronger emphasis on the sound that William is asking about. I come from the a town in the Midlands and, for instance, the last syllable of 'yesterday' is more heavily accented by some speakers there. I'l have to pop into a restaurant next time I go back and see how they say 'steak'.