You're mixing up dilution with forgone future growth.
Yes if a major with conservative growth prospects takes out a junior with blue sky (using scrip), then ex-holders of the junior get their blue sky potential "diluted" by their junior shares effectively being absorbed into the major.
However the idea is that if you can get say 30+% premium overnight via a t/o that will be a better return (annualised) than waiting for the blue sky to materialize and you can take the money or cash in the shares and move on to the next big thing.
EXS Price at posting:
63.0¢ Sentiment: Hold Disclosure: Held