How do you overcome growth hurdles?

Hi everyone! I'm new to yttalk but very excited about finding this forum and connecting with you all.
I run an educational channel in the mental health, psychology, addiction treatment space.

Growth has been fairly slow. Currently at ~1660 subs, ~800 views/day, ~130 subs/month
No matter how much content I put out these numbers always tend to stay the same and I have not seen in increase in our numbers for months.

All of the content I put out is optimized for search and I leverage suggested. Mostly everything on the channel is optimized, playlists, channel tags, long descriptions, started creating better thumbnails. I distribute our videos on launch to sites like reddit, email lists, and other social accounts. The only thing I really haven't tried would be to focus more on collaborations.

How have you overcome growth hurdles and do you have any thoughts on what I can do to continue growth? Thanks!
I also run an educational channel. The most important thing I did was establishing an identity and brand. People needed to recognize and distinguish my content simply from a visual point from all other creators in the fitness realm. It was easy for me because I did one thing no one else in YouTube's fitness sphere did: draw out all my videos.

Of course it's also important to make the content appealing, entertaining, and captivating. I try to avoid monotony and boring scripts as much as I can. And if I do have a boring script, my drawings are there to spice it up as much as possible.

End of day, most important part of my success is creating high-quality content that is unique.
I quit caring. For some people growth is easy, for others hard and for others simply non existent. The first group is the 1%ers. The ones that rise to the top. The second group is what I consider myself a part of. Averaging around 100 subscribers a month, and around 800-1,500 views a day. The last group is the group that complains and then often quits.

I do this thing until it is no longer fun. And right now I am in the fun zone. So what if I won't ever make it to 100,000 subscribers... At least I had fun creating content and being part of a community on YouTube.
I think "not caring" in the way you are describing it is helpful! If you focus tooooo much on numbers, you can't relax and that tension probably comes across in your videos. Someone who truly enjoys what they are doing often comes across in a very infectious way!
I find as long as I upload consistently and I stick to a general schedule, I find my views and subs slowly increase. I do overcome these "growth hurdles" where sometimes the views and subs stay stagnant, or even fall lower than it was the previous day or week/month. However I just stick to what I love doing, and not worry about it too much.
If your putting out regular new content and your not growing then that could mean that your old content is no longer getting the same views or watchtime. Maybe try making your older content more evergreen by editing titles, tags, keywords to something more relevant e.g. 'how to in 2018'.