I have a big red button on my VHF comm radio on my boat and if I press it every vessel within range will have their radio set off a loud alarm and my vessel name and location will be displayed on their radio
Pilots also have the option of doing the same thing with the ELT. There is a red guarded switch in the cockpit for manual activation. However, it wouldn't be difficult to imagine reasons why the pilots wouldn't have had the presence of mind to activate it (if it was part of their procedures) with the buffeting/g-forces, possible decompression, loss of power, wiring damage, manuals (& hot beverages) flying around the cockpit, etc.
Where is the battery for your boat's VHF? Where is the antenna? What happens if the boat overturns or breaks up before you have the chance to push the red button? On a boat, do you put on your life jacket before or after pushing the red button? Sometimes immediate self-preservation takes priority over long term preservation.