Having used Mastodon for a few years, I would say that it doesn't work like that. There's no reason to expect interaction unless you bring an IRL group, or stick close with a popular niche topic. Most people I interact with have an agenda, and don't need me for anything other than boosting their posts. Some are intensely hostile to anything other than standalone posts. Anyone replying across the platform is labelled a 'reply guy' and basically dissed and shunned. "Ultimate cancelling", I think.

Most of Mastodon doesn't want to support the rest of Mastodon AFAIK. There isn't a broad society with popular encouragement as you had with early Instagram, Twitter, and Reddit.

At the outset of popularity for the platform, a lot of long term users were very upset about popularity. To the day, those users are trying to discourage other people. If you post, they might even counter-post as cleverly as possible to attach disdain to anyone interacting with you.

Don't take any of it personally. It's not about you. Luckily you're not special in this regard. Post there if you want to, but never expect something beyond passing jerks.