I may have found an alternative solution to my blog's commenting system! 
The synchronization of comments from my Mastodon account. It's something I tried and abandoned, but I'm giving it another try after reading your comments. Well, I explain more on the blog and also share the source code:
Blog post, source code, and demo:
→ https://www.davidrevoy.com/article981/i-may-have-found-an-alternative-solution-to-my-blogs-comment-system
Bonus: Because I'm happy, here's a happy Mastodon mascot as a postman that I painted this morning.
#blog #selfhosting #php
@davidrevoy This is awesome! 
Given you said spam was a problem with the previous commenting system, does this mean you consider Mastodon to be reasonably free from spam?
I sort of live in fear that Mastodon might suffer an influx of bots. Especially given it's decentralised, so presumably any instance could contribute unless your instance admin defederates from them.
@ollie Thanks! Yes, I think the moderation and collective works of all user here with the report buttons makes the place pretty safe.
I received insult, p0rn, spam, but very rarely, and it was removed after a simple click on the three dots and reporting them. Actually, I wish this post will attract one or two post of this type. I'm curious if the API would list the message if I block an account.