I want to assume that a lot of individuals expressing disappointment over not having fanmerch made of them aren't aware of the commitments involved in producing physical merch, so here's some information to put things into perspective.
Through my own preferred manufacturers, here are the unit prices in USD for producing some commonly-found types of merch at conventions:
$1.00/sticker
$1.29/A4 print
$2.19/acrylic keychain
$3.41/acrylic standee
The above numbers reflect the most basic material qualities (eg. single-side printing, no holo, standard paper weight, etc.), and are all taken at a base MOQ (minimum order quantity) of 50. This means that there is a minimum investment of $60-170 in costs when committing to produce a piece of merch. If you'd like to play it safe, you'll also be paying an additional fee to have proofs mailed to you prior to production. I myself also care a lot for the quality of what I produce, so I always opt for heavier paper weight, kiss-cut stickers, metal keyrings, etc. All this to say, the estimates I provided above can only go up from here.
That's all before we take into account the work put into designing a piece of merch suitable for its form factor, colour correcting for printing, file setup for production, and of course, doing the actual illustration. Once the products arrive, there is also the matter of storage, sales forecasts, and relevancy: these 50 (or more) pieces of merch will now stay with the artist until they are sold. Do you have the confidence that you and your community will collectively buy 50 pieces of merch? Outside of an event like Offkai, where VTubers are the focus, will your merch have any relevance if it's displayed at other events?
With all this in mind, it should no longer come as a surprise that fanmerch usually feature very recognizable VTubers with a large fanbase, or the artists' personal biases. It really takes so much love to produce merch🥹🫶 So if you ever get to a point in your streaming career where you find fanmerch of yourself, please cherish the artists and know that they went through everything I outlined above to make that happen for you. And if you haven't gotten there yet, please use this as motivation to become a creator who inspires people to make merch of you!💪