Yes. I think your reaction is justified, with one important qualification: the CMB is extraordinarily strong evidence for the consequences inflation was supposed to produce, but not a unique fingerprint of inflation itself.
The ScienceDaily article is actually talking about a broader survey of physicists: it says no single answer to several foundational questions—including the standard cosmological model—got majority support. That sounds more dramatic than it is.
On inflation specifically, there are two rather different propositions:
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The early universe underwent some inflationary episode.
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We know what physical field/mechanism caused it and have a satisfactory fundamental theory of inflation.
The first has quite impressive empirical support. Inflation naturally produces a universe that is extremely flat and homogeneous while also generating tiny primordial density fluctuations. Those fluctuations should be approximately Gaussian, adiabatic, and nearly scale-invariant—and that is remarkably close to what the CMB actually shows.
And I think this is the point you're getting at: the CMB isn't merely saying "the universe looks smooth." The detailed angular power spectrum contains a whole pattern of acoustic peaks and their relative amplitudes. The measured primordial spectrum is very close to the sort of nearly scale-invariant spectrum that inflation predicts. The CMB measurements have therefore turned what was originally a rather speculative idea into a quantitatively successful part of cosmology.
Where the lack of consensus is understandable is that inflation is more of a class of mechanisms than one sharply specified theory. There are an enormous number of possible inflaton potentials, and some can be adjusted to reproduce the observed spectrum. The really distinctive additional prediction would be primordial gravitational waves, usually characterized by the tensor-to-scalar ratio r. Those have not been detected convincingly.
So I would put it this way:
There is much less consensus about what inflation is than there is about whether something inflation-like is a very good explanation for the observed initial conditions.
And there's an interesting asymmetry here. Theoretical objections—fine tuning, the absence of a known particle-physics realization, questions about the beginning of inflation and its measure, etc.—are legitimate. But those aren't empirical refutations. Meanwhile, the observational record keeps saying, in effect, whatever happened very early on, it produced remarkably inflation-like initial conditions.
That is why I share your surprise at treating "lack of consensus" as though it means the evidence for inflation is weak. The evidence for a particular underlying mechanism is weak; the evidence for the inflationary phenomenology is considerably stronger.
There is even a current debate illustrating exactly this distinction: recent work continues to test inflationary models against CMB constraints on ns and r, rather than simply asking whether the CMB resembles an inflationary universe at all.
In other words, physicists may quite reasonably be arguing over which inflation, why inflation, and whether something deeper replaces inflation without that being equivalent to arguing that the CMB doesn't strongly support the basic inflationary picture.
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