“Regurgitate/regurgitation might cover the “repeat phrases they heard on TV programmes” part of your description but you’d probably need to add something to capture the “set phrases” and/or “inconsistent” parts:
What he says is just “[a series of] regurgitated [phrases//factoids//non-sequitors/sequuntur]."
What he says is just “[a series of] {boring/nonsequitous/inconsistent} regurgitation."
Actually, perhaps my favorite word (from @jimm101 's good answer) to use with “regurgitated/regurgitation” in your context would result in:
“What he says is just [a series of] regurgitated platitudes.”
(from ‘Information Management for Development Organisations’ by Mike Powell, via ‘Google Books’}
And
“What he says is just [a] regurgitation of platitudes.”
(from ‘The Southern Partisan, also via ‘Google Books’)
Regurgitate
Transitive verb
1 formal to repeat facts or ideas that you have heard or learned without understanding them or thinking about them for yourself
(from ‘MacMillan Dictionary’)
For two food words that have slang meanings similar to the "’empty, irrelevant, talk” part of your question that would go well with “regurgitated” to capture the (imo, important [see below]**) “often repeat phrases” part of it and which would create a perhaps fitting “double-entendre” image to help reinforce your message, you could consider “regurgitated tripe” or “regurgitated baloney”:
*… but what he says is just regurgitated tripe/baloney.”
(here’s an example of the use of “regurgitated tripe” in a political context from ‘Sex and Murder’ by Douglas Allen Rhodes and there’s one here for “regurgitated baloney” from the ‘Daily Labor Report’, both via ‘Google Books’)
tripe n.
1. the first and second divisions of the stomach of a ruminant, esp. oxen or sheep used as food.
2. Slang. something, esp. speech or writing, that is false or worthless.
[1250–1300; ME < OF]
baloney or boloney n.
1. Slang. foolishness; nonsense.
2. BOLOGNA .
--- interj.
3. Slang. nonsense.
[1915–20, Amer.]
(both definitions, with emphasis added, from ‘RANDOM HOUSE KERNERMAN WEBSTER'S College Dictionary’)
**(I see the "often repeat phrases" part of you question as important because it's what makes it different from the questions cited as possible duplicates)
