Ah, my favorite time of year, the wave of low-effort README and library version update PRs.

This annual garb is basically like a vacation for volunteer/FOSS devs. Close shop/PRs, open again after a month.

Does this still exist? I thought it has a horrible reputation where inexperienced people produce a high quantity of low quality contributions, cause unbearable workload to maintainer and a lot of anger.

Yes, contributing should be encoraged, but contributing a lot in a short period of time is absolutely the wrong incentive for newcomers. You need to lurk around a longer time, following the mailing list, chat, committed changes of a project carefully before starting to contribute. Replying the questions might be better first step than sending in changes.