I agree 100%. Infinity Ward made a great game. Really tough to match that. It isn't perfect but it is the best COD title since 2007's Modern Warfare.
The movement and player mechanics were a nice refinement of all of the prior COD titles. MW 2019 has incredibly fluid movement and the player feels like he maintains momentum at all times. Conversely Treyarch's movement is jerky, fast at times but sliding, jumping, and throwing grenades are all slow-there is no sense of continues momentum. Treyarch's games are marked with a more arcade-like shooting quality-the game simply feels more casual.
The MW 2019 multiplayer maps, while not all great, all have fully explorable interiors. Infinity Ward tends to to this with their maps whereas Treyarch's games are characterized by locked doors and hallways. The interiors constitute lanes in Treyarch's maps while MW2019's lanes are predominately exterior with fully traversable buildings to divid the lanes. It is a seemingly subtle but huge difference in their approach to map design.
Finally the sound design in MW2019 is just lightyears ahead of Black Ops. MW2019 is loud but the guns sound and feel real. The guns in Black Ops don't sound like they have evolved much from the 360/PS3 titles.
I know that the Pro and hardcore scene did not take kindly to MW2019-I think with a little refinement the game could do really well. The Gunfight competitive mode in particular is excellent. The pros took issue with the removal of dead silence as a perk-a change I think was for the better as it encourages a different play style and punishes players who try to make big solo plays as opposed to working with their team. The other major change was the removal of the minimap-this makes team communication and callouts more important; another change I see as a net positive. Finally people have complained about the SBMM implementation resulting in closer matches-another positive change that people seem to hate since top 50% players lose the opportunity to stomp on lower skilled players in matches. SBMM was in prior titles but seemingly had a better implementation in MW2019. I argue on behalf of the pro/hardcore scene in nearly ever game (Halo, Gears, Smash, etc) they typically know what changes need to be made but with COD the pros and hardcore players seemingly just want the game to cater to a more solo playstyle. I don't like that-a team based shooter played a high-level shouldn't be so focused on solo play. Then again Pro COD is only just now making the leap from console to PC but they are still forcing controller only so what do they know. If anything I think they should look to COD4 Promod for pointers on moving the game forward in the professional world.
Activision needs to slow down on the COD releases. Move to COD as a platform, it will reduce expenses and drive an increase in income allowing the monetization of the game's tail for years. Look at all of the success titles like Fortnite, Destiny, Apex, CS, and even Warzone had. This frees up development resources to make other games. Keep supporting MW2019 w/ battle passes, new weapons, multiplayer maps, and Warzone content. Add Zombies as another vehicle for cosmetic micros. There isn't any reason to not treat COD as a platform and continue iterating. Maximize revenue on the title for a few years before moving onto a new one.