For those who want to follow the conversation, you can do so here on steemd.

I'm just asking that he lets me do my thing to help build a strong social network.

I agree with his opinion that you were not building a strong social network. Posting image after image seems like spam to me, as I've already mentioned. Spam on a social network = bad.

when I humanly can't create more than 15 custom welcome signs per day

It would be very, very easy to program this process to do it nearly instantly. If you were rewarded for this, others would do it also in an automated fashion.

A welcome message that's just an image is, to me (and apparently others like Smooth), not a genuine welcome message. I get that's a subjective impression, which leads to my next point.

I played by the rules

So did Smooth or anyone else who flags your approach. Saying "no one else flagged" me isn't much an argument (IMO) because smart new users aren't about to start flagging things on their first post.

The fact the there existed welcome bots before my initiative indicates that there is a market for welcoming new users.

Take a look at their reputation scores now (@wang, for example, is a -16). That should tell you something about how this network feels about welcome bots or activity which mimics (or can easily be reproduced by) a welcome bot.