BR, I appreciate you detailing out your reasoning, some of which I agree with, but I am going to push back here too. I think a lot of what you are saying is exaggerated or inaccurate. I definitely am not a CX apologist and have no ties to the developer. I am am, however, a community stakeholder who walks through here constantly.
1) Mere yards away is historic street-gridded East Cambridge. There are multiple access points from there to CX, and this developer is paying to extend First Street to reconnect CX to this dense neighborhood that abuts it. Some effort, yes. Enough effort, no: there should have been better pedestrian connections including ones that allow peds to completely avoid the McGrath/O'Brien
2) These developers participated in the land swap deal that plunks a transit station directly into their neighborhood. You can get downtown in minutes from trains that actually have decent headways now that the two GLX branches are both open. Should the developer get a ton of credit here, No. But WTF suburban office park has a multi-branch transit station in it with a direct connection to the urban core? Reality: this spot is well connected by bike, bus, and rail transit. It is flat out not true that everyone gets here by car. You can literally watch a stream of people walk from the GLX station to the lab buildings in the morning.
3) There is a TON of papered-over ground level retail that retail brokers are trying to lease. Should it be leased by now and could they be trying harder, maybe. But the retail presently activated is like 15% of what it is designed to be. I am 100% with you that all typical errands should be able to be reached by CX's residents within 5 minutes. There should be a grocery store, pharmacy, several other reasonably priced meal options, maybe even a library branch some day. So, yes, it's not acceptably built out yet. But show me an office park anywhere that has as many retail stalls as CX. I am not going to go count now, but I would be shocked if there were fewer than 25 retail storefronts within these buildings, nearly all of which are papered-over. There is a problem here, but it is not specifically the one you are calling out.
4) The park is supposed to be fully lined with buildings. Some of them are not built yet. They need to be, IMO, for the park to be properly hemmed in and with a fully active streetwall. The developer has clearly established plans with (mostly) prepared lots expecting to be built upon. So give them a bit more time. There was a pandemic that disrupted things, the interest rates are through the roof, etc.
5) Big floor plates and big fat lab buildings: A) I hate lab buildings, B) the life sciences industry is world class in Cambridge and is our golden goose. It is only natural that a live/work/play neighboorhood is going to have to deal with/accommodate the life sciences industry. Charles Street is wonderful, but labs don't fit in narrow 19th century brick buildings. The problem needs to be framed differently: HOW can we come up with lab building designs that are multi-use and don't suck nearly as much as the ones we're building. NOT, how can we tell Sanofi, Bristol Myers Squibb, Philips, etc, to get the F out. It does not make sense to kick them out - they actually have people in the office, unlike other types of businesses these days. Let's give those people a place to live, places to have recreation, and shops to patronize.
6) People: if you look at the CX master plan, you will see that there are roughly half a dozen additional residential buildings. They are not built yet. When they are, there will literally be thousands more people here. That is a game-changer. The retail slots will fill out.
So, I go back to my original point. What we see from CX has elements of laziness in design, implementation, and neighborhood innovation. It is not sufficiently "there yet" in my mind, but I am rooting for it to get better. But I refuse to accept arguments that it is suburban or anti-urban. It is not those things.