The paper referenced in the question try to demonstrate that the tangle cannot resist to a 51% attack. Nothing really new here.

The position of the Iota Foundation is to favorise a *stable organic growth* of honest transactions (as founders said multiple times on discord, reddit, ...)

Some members of the community suggested to include a spammer on IRI nodes to artificially increase the tps. (suggestion discussed on discord a few weeks ago)

IMO, the referenced paper is a bit misleading in it's formulation (as demonstrated by the question of the OP). An *not very attentive* reader may understand that all honest nodes MUST constantly use their full hashing power to secure the network. But the paper talks in fact of *assiduous honest majority* (of nodes) : a concept equivalent to the cumulative hash power invested in honest transactions. 

In other words the conclusion of this paper is something like : "With the currently proposed tip selection algorithms, the total hashing power invested in honest transactions MUST be greater than the total hashing power invested by an attacker to prevent double spend."