1) Chatbots are never going to be perceived as safe or effective as humans by default, primarily due to human fiat. Professionals like counselors (and lawyers, doctors, software engineers, etc.) will always claim that an LLM cannot do their job, namely because acknowledging such threatens their livelihood. Determining whether LLMs genuinely provide therapeutic value to humans would require rigorous, carefully controlled experiments conducted over many years.
2) Chatbots definitely cannot replace human therapists in their current state. That much seems quite obvious to me for various reasons already argued well by others on here. But I had to highlight point #1 as devil's advocate, because adopting the mindset that "humans are inherently better by default" due to some magical or scientifically unjustifiable reason will prevent forward progress. The goal is to eliminate the (quite reasonable) fear people have of eventually losing their job to AI by enacting societal change now rather than denying into perpetuity that chatbots are necessarily inferior, at which point everyone will in fact lose their jobs because we had no plan in place.