I am aware: "you" was used to indicate the moderating organisation engaged here, not you as a single person. Sorry for the confusion in that. "You" is used in general to refer to the organisation unless specifically marked otherwise.
This is not the matter here though. While you are not interested in using IRC, and you don't have to, it is unnecessary and frankly damaging to force people to this website and ruin a perfectly functioning channel.
The proposal is to either let us use the #letsencrypt (and of course mark in the topic that the only official help is available in this website) channel in unofficial capacity or change the bot message to also mention ##letsencrypt. Neither costs you anything and frankly both actually benefit the organisation and foster inclusive and low threshold community engagement and community support.
Because you have opted to make this decision without consulting your community and userbase and you have no public statistics, that is again the personal opinion of the moderating organisation, not the community as a whole. Also simply because people don't want a perfectly good channel ruined does not mean closing the channel was the correct decision: your logic does not follow in any way from that since spam and abusive behaviour can just as well appear on this website. Also to make it clear, I am not in any way affiliated with anyone else who might have posted here or on IRC regarding this issue. Suggesting such connection is absolutely unwelcoming and borders on harassment and frankly, the decision to close the channel breaks your own guidelines by harassing IRC users and forcing your identity on them since IRC is an important aspect of people's identity.
Please review the decision to close the channel and open #letsencrypt again for discussion or change the bot to point at ##letsencrypt. The first one is is preferable.