Why do viruses last longer on hard surfaces, like glass, than porous ones
The paper you cited is not about survival on smooth versus rough surfaces; it does, however, mention discrepancies in survival on metallic versus non-metallic surfaces.

From the article you cite (Piercy et al., 2010):


  The lack of recovery of virus from metal substrates may be attributed to several factors; previous work (Sommer et al. 1999; Pawar et al. 2005) has shown the binding of micro-organisms to metal surfaces to be poor because of the high surface energy, high electronegative and hydrophilic properties of metal. Other research has also shown that positively charged metallic ions such as copper and silver have a high bactericidal activity (Friedman and Dugan 1968; Bitton and Freihofer 1977; Slawson et al. 1990) and hence by extrapolation may also have a high virucidal activity.


In short, it isn't exactly clear why viruses in particular might have poor survival on metal, but the electrical and chemical properties of metallic surfaces, as well as biological activity of metallic ions that are constantly leached from alloys like steel are all candidates.

The claim may also not apply to all viruses, and the results are not consistent across labs. For example, Sagripanti et al. 2010 find no effect of surface material (aluminum alloy, rubber, or glass) on Ebola, Venezuelan equine encephalitis, Lassa, and Sindbis viruses.

References:

Piercy, T. J., Smither, S. J., Steward, J. A., Eastaugh, L., &amp; Lever, M. S. (2010). The survival of filoviruses in liquids, on solid substrates and in a dynamic aerosol. Journal of applied microbiology, 109(5), 1531-1539.

Sagripanti, J. L., Rom, A. M., &amp; Holland, L. E. (2010). Persistence in darkness of virulent alphaviruses, Ebola virus, and Lassa virus deposited on solid surfaces. Archives of virology, 155(12), 2035-2039.

Bitton, G., &amp; Freihofer, V. (1977). Influence of extracellular polysaccharides on the toxicity of copper and cadmium toward Klebsiella aerogenes. Microbial ecology, 4(2), 119-125.

Friedman, B. A., &amp; Dugan, P. R. (1968). Concentration and accumulation of metallic ions by the bacterium Zoogloea. Dev. Ind. Microbiol, 9, 381-388.

Pawar, D. M., Rossman, M. L., &amp; Chen, J. (2005). Role of curli fimbriae in mediating the cells of enterohaemorrhagic Escherichia coli to attach to abiotic surfaces. Journal of applied microbiology, 99(2), 418-425.

Slawson, R. M., Lee, H., &amp; Trevors, J. T. (1990). Bacterial interactions with silver. BioMetals, 3(3), 151-154.

Sommer, P., Martin-Rouas, C., &amp; Mettler, E. (1999). Influence of the adherent population level on biofilm population, structure and resistance to chlorination. Food microbiology, 16(5), 503-515.