Cheap flights and accommodations were mentioned.

Flying is an unusual product that gets cheaper over time. Supply has increased.

Airbnb has had an impact on hotel pricing and availability.

Almost every product gets cheaper over time.

Inflation says otherwise.

Inflation does not change the real cost of goods and services, only the nominal cost.

And the costs of flying and accommodation have actually gone down in real terms.

That's not true outside of theoretical context, much like the concept of efficient markets. In reality, inflation does change the relative real costs due to the mechanism by which inflationary monetary policy is implemented: debt. Products that rely heavily on debt (construction, airlines, etc.) will be affected by inflation differently from products that use little of it (technology, fashion, food service, etc.)

That's an interesting, but unusual perspective.

It's commonly understood that not all prices change in lock step, but "inflation" is the general or aggregate change in prices, usually based on the change in the purchasing power of money. Choosing to finance or pay cash for a car or a house doesn't change the price of the item, just your cost of acquiring it - it exposes you to expected future inflation, in addition to the current price, because you will be paying back the incurred debt with less-valuable future dollars. The interest you pay also pays for the use of someone else's money for the period of the debt.

Note, too, that inflationary monetary policy is also implemented by creating money in other ways, like a printing press, and inflation can also be caused by supply/demand shocks, like changes in supply/demand of fundamental commodities, like oil.

I just don't think this is true. I mean, I see your point, but it just doesn't seem to be that significant in practice. Possibly because the interest you get at a bank has inflation priced in. In reality, more or less everything is getting cheaper in real terms. There are some exceptions, like housing (urban land), and services (people's time) but these are exceptions.