The change is seamless. All redirects are being fixed (including quite a few that were missed by people when these were moved in the past). We get these in dribs and drabs over at WP:RM, a few a week. Easier to just clean them up. As for projects, they do not overrule the policy of WP:NAME and Wikipedia:Manual of Style (infoboxes)#Design and usage. Standardization is a good thing. We will continue to grow; these boxes will be used in the future and changing them means when we reach 6 million articles, the future ones that would have used the prior name will use the proper name. Moreover, when people seek to create new infoboxes, just as often or maybe more often they do not learn what the title should be by going to the policy but by looking at where existing, similarly situated templates reside, and by standardizing we foster the creation of new templates at proper names. Please also see Wikipedia:Don't worry about performance.