Most of the stock gravel bikes I’ve seen are not really geared for stiff climbs, at least for those of us who do not have the genetics of a tour de France climber. As an example, the Canyon carbon fiber Grizl CF SLX 8 has a front chainring of 40T and a rear cassette of 10-44 giving a lowest gear of about 30 gear inches. This retails for $6500. A Hardtail mountain bike might have a front chainring of 32T and a rear lowest gear cog of 50 T (or higher). I guess one question is what you will be using the bike for.