  Motivated by the recent release of new results from five different pulsar
timing array (PTA) experiments claiming to have found compelling evidence for
primordial gravitational waves (GW) at nano-Hz frequencies, we consider the
prospects of generating such a signal from inflationary blue-tilted tensor
power spectrum in a specific dark matter (DM) scenario dubbed as
$\textit{Miracle-less WIMP}$. While $\textit{Miracle-less WIMP}$, due to
insufficient interaction rate with the Standard Model (SM) bath gets thermally
overproduced, inflationary blue-tilted gravitational waves (BGW) in compliance
with PTA data, conflict cosmological observations if reheat temperature after
inflation is sufficiently high. Both these issues are circumvented with late
entropy dilution, bringing DM abundance within observational limits and
creating a doubly-peaked feature in the BGW spectrum consistent with
cosmological observations. The blue-tilted tail of the low-frequency peak can
fit NANOGrav 15 yr data, while other parts of the spectrum are within reach of
present and future GW experiments.
