Battery life is the main reason for two way wireless, but there are benefits to two way comms they are more secure when it coms to jamming, the panel polls the detector instead of the other way around, diagnostics like range ect, you can put the detectors in walk test mode from the panel just to name a few.
I use Alexa for home automation, I have given much thought to using Alexa to arm and disarm, she recognises my voice over others in my family. I may use her to part set arm only but at the moment not disarm.
I have been experimenting with wireless locks (not for home) and part of that I have purchased some of these cheap wireless locks to take apart and redevelop. One of them came with an App that has an Alexa skill, I thought well it may be useful so I tried it. To use it you tell Alexa to unlock the door, Alexa then asks you for a code, you say the code and the door unlocked. So anyone in earshot can here the code and unlock the door, not so secure.
I do use my alarm to switch on various outputs though, when the alarm is armed all the lights in the house and outbuildings are switched off, when I come in the hall light comes on so I can find the keypad, when my system is armed fully my heating switched off I can override this function if I am just poping out for ten mins
You can integrate your CCTV to your intruder app, but I haven t bothered my CCTV app already tells me what I need to know, I dont mean it lets me know if something is moving in my garden trees are always blowing around why do I need to know that? it tells me in a person size object (not next doors cat) is approaching the house, it alerts me before the intruder so no need to integrate.