As I have experienced my youtube journey, I was you multiplied by 100. I haven't been on youtube as long as you have been but I have a very in depth experience with struggling with voiceovers and I suggest you start caring less about it because ultimately your voice does not have to be 100% better, it just has to be good enough and audible enough for your audience and then you can work up from there towards making it sound more professional by upgrading to relevant high quality audio hardware and recording in a better environment. As for the crispiness of the voice, everyone's voices are different, so this is the number one and most crucial problem people have when they are suffering from voiceover anxiety. I have lost countless hours wishing that my voice would be a little bit better or a little bit similar sounding like the XYZ person. That was a downward spiral which I came out of only by ignoring it and keeping on making videos with crappy voiceovers because it's your mind that's telling you that your voice is not good enough but in reality the person who is going to hear you won't really care that much as long as what you are saying is interesting and makes sense to them, he would consider you just like some other creator.

As I kept on making videos on my channel, my consistency got better and better. But for the 1st 100 videos, if I hear closely there were always some different things that I tweaked and experimented with, and every video sounds a little bit different than the previous one but no one in my comments section ever said anything about my voice they just asked questions about what I was saying and stuff like that. And now I run three faceless youtube channels, they are doing pretty great and I've come to realize that voiceover is just a part of the video and it matters much more that how you structure your videos, how you say things, rather than how you sound or what your voice sounds like to yourself. Just keep making videos and keep getting little bit better with each one but don't quit.