The entire “indie” digital art NFT scene has been on Tezos for about a year. If you read the Ubi announcement closely, you’ll see they intend to use the same marketplaces used by this art scene for their transactions – in other words, the Ubi stuff will be traded outside of Ubi’s marketplace. Also, Ubi is a corporate sponsor of Tezos and one of the primary nodes/stakers, so the company has a vested interest in helping Tezos scale. There’s some info in this Twitter thread.
This entire blockchain/NFT space is new and speculative. All of the BTC/ETH/Tez, etc. services are adapting and learning as they do so and there’s a baseline lack of stability in the entire ecosystem because of it being so new. I would say it all feels akin to the web circa 1994. About 1/2 the time, I feel certain it will all collapse in 6 months, the other 1/2 of the time it feels like it actually might be the beginning of a new backbone to online commerce. I suspect a lot of the early corporate involvement will feel very much like the Second Life rush in 2006/2007.
 I say “indie,” because the low transaction fees on Tezos have enabled a lot of people who aren’t BTC/ETH wealthy to participate. There’s a “Tezos fountain,” where people without access to traditional banking can receive a few Tezos to get started with minting/selling their art. This has enabled a ton of really talented artists from resource-poor backgrounds (and from places that aren’t strongly connected to US and European banking systems – a lot of folks from the global south) to participate.
 One of the larger ones: https://objkt.com