Short answer
Yes. Mechanical diamond grinding is the professional standard for preparing concrete, because it creates a consistent, coating-ready profile and removes surface contamination. Acid etching — the shortcut — is inconsistent and a leading cause of coating failure.
What diamond grinding does
Grinding uses diamond-segmented tooling to abrade the top layer of the slab, opening its pores and creating a uniform profile the coating can mechanically lock into. It also removes old coatings, sealers, glues, and surface contamination in the process, leaving a sound, clean surface.
Why acid etching falls short
Acid etching relies on a chemical reaction that's hard to control and doesn't work evenly across a real-world slab — especially one with any contamination or a hard-troweled finish. It can leave residue and an inconsistent profile, both of which undermine the bond. It's popular because it's fast and cheap, not because it works well.
The payoff
Proper grinding is the difference between a coating that bonds for a decade-plus and one that peels. It's a big part of why a professional install costs more than a DIY kit — and why it lasts many times longer.