This is all great. But the real improvement in C++ skills can only come from real work, solving real problems. No amount of time spent on discord/slack, blogs

This is all great. But the real improvement in C++ skills can only come from real work, solving real problems. No amount of time spent on discord/slack, blogs or conference talks can substitute the real work experience. When you learn something from a blog, book or conference talk, you should go home and apply your new knowledge to the problem at hand, realize the pros and cons, understand the trade-offs. Without this work your knowledge is only skin deep.