FYI, the shows aren't the sole moment of enrichment for tigers throughout the day, which is what you're inferring there.
Bit my tongue for a hot minute there, will keep it short and brief:
1) Tigers can be as equally as enriched in a no contact environment as they can be with hands-on environment, it just takes a lot more effort.
2) Risk appetite and the current business plan are the two dictators for hands-on vs no-contact. This current Dreamworld has a low appetite for risk from both a comms and workplace safety perspective. The current Dreamworld hasn't placed animal exhibits high in their current business plan, hence why so many high-profile names have since left. Ergo, the transition to no-contact was inevitable.
3) I'd say 90% of folks out there get the handler/animal relationship and the inherent risk in the same way if you sign up for the Army you might anticipate being shot at. It comes with the occupation. There's a lot of benefits to that relationship, it's easier to enrich the animals (for example, animals can go beyond enclosures in a controlled setting, it also exposes them to foreign noises, smells, different environments and makes them more manageable), fostering litters is far easier, opens up opportunities for additional revenue for the program (photos etc.) which then in turn raises additional exposure in market to the cause, etc. etc.
My belief is that it's too much risk mitigation, and the money spent transforming an entire compound that was never designed for no-contact would've been better spent in better PR and more education/comms about the benefits of the program and what DWF was doing for conservation. That money would've generated an ROI.