man I’m only half, but I’ve had almost this exact same experience. Growing up with both MTG and 40k, I was often the only person of any color whatsoever at events, and depending on how white I was (or wasn't) presenting at any given time, my experience would be dramatically lessened.
What white people (especially in the 90's in California) generally knew about “Mexicans” (using this as a broad brush because my mom's family has been in California pre-dating the Spanish colonization and it didn't matter if you were Ecuadorian, El Salvadorian, or even Brazilian and speaking Portuguese - you were all 'Mexican' to the white crowds) was “Yo Quiero Taco Bell”, Cheech Marin, and Speedy Gonzales.
I was at a Magic tournament during the Tempest block when I had just turned 14; things were going great, but some dude at a table over from me was making racist jokes about their “spic” gardener - a buddy of mine tried to tell them to shut up, that it wasn't cool; he could of stopped there, but instead he added the quantifier “His mom is Mexican!” thinking it would - I don't know, put them in their place? Well intentioned I guess.
I ended up leaving early because the harassment that followed was so bad - not just from the instigator, but others. I'm 14 and trying to concentrate and 'OOOH you better not lose to the wetback!' being shouted from other tables. Cheech voices everywhere.
For YEARS after I was mad at myself for not trying to be the bigger person - and then I realized there was no winning with these people. I was always going to be 'other' (and I should point out, when they thought I was white there was no problems at all) as long as the perception of me being non white was there.
It’s been almost 30 years and things really haven’t changed that much, so anyway if I'm ever un-apologetically gleeful about white people being upset by ”forced diversity“, you can probably guess why.
