Seeing as Riot Meddler specifically stated that they care about hostage holding champion select, I'd say that they actually do.
"Working on a solution" is how the world works. Large systems take time to get into motion. Bureaucracies are slow to change, and companies with limited resources cannot drop everything to try to fix a single problem in one attempt.
Take a second to imagine the amount of support tickets they receive, I'll give you a hint: it's over 100 thousand in less than an hour. And that's not even at peak times. There's probably a massive number of those that are reports of trolls and toxic players. Regardless of the %, even a small amount is still going to be a large amount throughout the course of an entire day. They cannot just stop and respond in-depth to every player who reaches out to them, they've even said they tried that before and it was impossible to maintain.
tldr; Give them time, things aren't magically fixed overnight. And it's more practical for them to take their time coming up with the right solution rather than run around putting out fires so much that they can't even work on anything else as well.