I think it will change things but that could also be a good thing if people are made to think more about their liability towards others when doing things like this.
Austria is becoming overrun with Instagram-type tourists who have seen particular locations and want to go there, often appearing in completely inappropriate clothing. There are a lot of issues which I won't go into here which would be a very long post.
Basically there are more and more fatalities, 300 in Austria last year, because more and more people are attempting hikes and climbs without sufficient experience or physical condition. Most of the fatal accidents are caused by slips and falls or are heart attacks.
There are a few social media groups appearing where people post hikes they are going to do and invite others to join and they can sign up to join while ticking a box to say they are responsible for themselves because the person organizing is not a mountain guide and not acting in the capacity of mountain guide. But you can't waive your liability away like that if you organize a hike like that and some of the people are not fit enough/well-equipped enough to do it.
If this makes people think more about what they are doing, where they are going and who they are taking with them, it's a good thing.
Mountain rescue is constantly being called out to people who have tried to hike mountains in inappropriate clothing and inappropriate weather conditions. Do people not even look at the weather forecast???
If you're an experienced mountaineer and you take someone with you who has little to no experience (as in this case where Kerstin had not done a winter tour of this kind before), then you, as the experienced person have to take on a lot of the responsibility for ensuring that the person has the correct equipment, for assessing weather conditions, for making the decision about turning back if it turns out the person is struggling or clearly not up to completing the entire climb and descent safely even if at that moment in time they seem to be ok.
The less-experienced/physically less strong person also has to bear some responsibility for asking questions about the tour and thinking about whether they can manage the tour and also keeping the other person/people informed during the tour about whether they can manage or not, not trying to keep going when they are really struggling. However, I can also understand how it can be nigh on impossible to say "I can't go on any more" or "I won't make it to the summit so we have to turn back" to a personality like Thomas P. If this ruling sends out a strong message to people like him, good.
Of all the accidents and fatalities which have occurred in Austria in recent years, it's interesting that it's this one which has been taken to court and had this result. I think there are a lot of things which are unexplained, especially the state in which she was left which bore no relation to what he described. The alpine police knew something was very amiss here from the beginning and that's how it got this far.