Comments are always optional as are "likes" for members. Guests, or those who open the site but don't login can't leave either.
For me, a like or a comment is a bonus: Even if it is a bit critical.
I no longer have any time to write, but when my grandson who will be three in July goes to pre-school and school I hope to have time to write some more.
I try to leave a comment on what I've read, but if everything I want to say has already been said by others, I don't see much benefit in merely being repetitive. If all I can do is leave negative feedback, I usually refrain from commenting unless it is to complain that the chapter was too short. (Ask Carlos!)
My position on this has evolved over time. Time constraints forced me to change to this position as earlier I wanted everyone to comment, no matter what.