Stealth is a viable option in GTA Online Heists.
Now, stealth isn't for every player. In fact, most players don't have the patience to execute GTA Online Heists using stealth (such as in the Silent & Sneaky approach in the Diamond Casino Heist). There is an argument to be had where stealth isn't as fun as going guns a blazing, but that is a subjective matter and not relevant to its viability.
The viability of stealth in GTA Online Heists does depend heavily on who is doing the heist. If there's one player that's notoriously terrible at stealth within a squad, then stealth won't be a viable option in that situation. It's all about context, but in the right situation, stealth is a viable option.
Is stealth viable option in GTA Online Heists?
For some players, the stealthy approach to heists is more difficult than the other options. This means that for some players, stealth is a less viable option. However, from an objective standpoint, stealth is a viable option in GTA Online Heists. It might not be the best option for every heist, but it does work and some players do prefer to farm it with this method.
The advantages of stealth
The first advantage of taking the silent and sneaky routes in some GTA Online heists is that the player can save money on ammo. Players will still have to kill some enemies, but the efficient methods involved with the stealthy approach mean that the player won't have to use too much ammo to do so.
The second advantage of using a stealth approach to GTA Online heists is that weapons with suppressors become more usable. As the name would imply, a suppressor can reduce noise, which isn't particularly useful in situations outside of stealth (especially when it directly competes with other upgrade options).
The final main advantage of this method is that it favors players with a more methodical playstyle. It doesn't rely on quick reflexes or mindless shooting as much as alternative methods do, which in turn allows these players to still have a viable option in grinding out these heists.
Stealth is viable in GTA Online heists
Stealth is viable in GTA Online heists, but it isn't necessarily the best method for all players. GTA Online players need to remember that it's good to have a viable alternative as opposed to one method that is universally better than the other. The Silent and Sneaky approach in many heists is viable, but a player should consider the advantages and disadvantages of using stealth beforehand.
The disadvantages of stealth
The most readily apparent disadvantage to using stealth in GTA Online heists is that random partners are bound to screw it up. If a player doesn't know the experience of their partners, they have no way of knowing if they'll be competent enough to handle a heist with tact and composure.
The second most obvious disadvantage is that explosive weapons aren't viable in most scenarios. If a player wants to complete a heist efficiently whilst using stealth, then they shouldn't alert every guard in the building of their presence.