A service pistol has one real requirement: To be ready at all times for personal defense. I suppose one can make a case for an 'offensive' use, in house clearing or tunnel work, but the main purpose is personal defense. One does not intentionally use a pistol as a primary weapon in an assault. Now the rumor is the Government Model in .45 ACP is insufficient for this purpose. One also reads the Bible isn't trustworthy. Or that Democrat care about 'the people'. One reads all sorts of silly things on the internet and even in person from those who specialize in ignorance and call it 'inside information'.
The Government Model was used by the Armed Forces of the United States for a bit over seventy years as the standard service pistol. Additionally, it is one of very few pistols still being manufactured in more or less original format for over one hundred years. (The others being the Smith & Wesson double action revolver, and the Colt Single Action Model P. There are probably some others, but I cannot recall them.)
The Government Model does have some limitations, especially for semi-trained shooters. The 'cocked and locked' nature of the beast lends itself to negligent - 'premature'? - discharges if the shooter is not on top of the matter. The .45 ACP cartridge can be a bit intimidating in recoil - usually 'perceived' rather than 'absolute' recoil - to an inexperienced shooter.
Is it the only 'useful' service weapon sidearm? Probably not. There are others that seem to suffice. I carried a Glock for several years, the result of my agency deciding I should. It was 'okay'. It did well enough; I qualified with it and it was reliable. I was less than impressed with the 9x19 round; and the gun has all the personality and 'soul' of a mass produced hammer. But it is okay.
Still, I favor a Government Model. I rather feel most adequately prepared with such a device. My second choice would be a classic era K frame Smith & Wesson in .357 Magnum. Others may do as they feel suits them.